UK DTI applying generic standard to test hair dryer for conformity
Dear subscribers, I have read a news regarding on 3 Sept 02, UK Department of Trade Industry (DTI) applied EMC Generic standard EN50081-1 Radiated Emission to test for compliance on a AC Hair dryer, which claimed to interfere TV reception. The hair dryer failed the test and the importer was prosecuted by violation of EMC Directive. Should the product be covered by EN55014-1 already? Please comment. Regards Paul Chan This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
Re: single fault conditions
Hi Brian: The environment being considered is a switching power supply. The technique that safety agencies use to simulate a SFC on a power FET does not seem, IMHO, to simulate the actual failure mode of the device. To wit: when the mosfet fails short, it blows itself open; so the amount of current sucked out of mains, e.g., the PFC FET, would probably open the component after a few input cycles. But if I apply a direct mechanical short (source to drain), current is being forced to flow until the fuse blows, or until some series trace or component opens. The shorting of a component does not test that component. Instead it tests the remainder of the circuit for (safety?) weaknesses in the event of a short (or near-short) of that component. I suppose the opening of a circuit does test for the component failing in the open condition. But, the effect of the open-circuit is to test the remainder of the circuit for (safety?) weaknesses. So, shorting or opening of a component does not test the component but other parts of the circuit. In general, the termination of fault tests should be not only repeatable, but should be understood so that the parameters that make the termination repeatable are under control. The operation of a fuse is a good termination of a fault test. A cascaded fault of another component may not be a good termination of a fault test because the safe termination may depend on unknown or uncontrolled component characteristics. The Bad: some FETs fail very violently, and can actually be a fire hazard and/or shock hazard in open-frame switchers; but if the FET itself does not provide the short circuit, we will never know Switchers generally drive the switching FETs with a pulse-width-modulated waveform. One way to introduce a fault that tests the FET is to simulate a 100% duty cycle pulse by applying a dc voltage of the same voltage as the PWM signal. This will turn on the FET continuously, and you should get your spectacular failure. The Good: providing a continuous (mechanical) short will reveal if there are other components in the current path that could be cause the unit to fail in an unsafe mode. Although, according to QA records, these components have never failed, so it can be both demonstrated by design equations and empirical evidence that the SFC test does necessarily demonstrate anything relevant... Uh, no... I don't think you want to base your fault-condition safety on empirical data that the fault will not occur. I have never seen the fault of basic insulation in the field, but we nevertheless account for the failure of basic insulation with either grounding or supplemental insulation. There is nothing like a test. The Ugly: Safety testing results in design corrections that do not increase product safety. I would argue this point. I have not seen undue design corrections due to a fault test. So would it be legitimate to over-drive the gate, forcing short circuit current to flow through the FET, but not to apply a mechanical short across the component? Yes! But, unfortunately, some components do not lend themselves for such testing. Capacitors are a good example -- almost impossible to induce a fault. Best regards, Rich This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
RE: EN55022:1998 + A1:2000
Dave Cuthbert write the point at which ferrites are placed will not always have a common mode impedance of 50 ohms. Here's An example: a large DUT has a 1 meter long cable that connects Not always; make that rarely. Comments about the 150 ohm impedance are on target. That might be difficult to hold to. I can see the entry needing to be a bump of not more than 15 ohms at the high frequency end, and increasing per unit length attenuation with distance from the entry. Cortland This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
Re: Telephone Book for Iran, again
David et al, I've checked further and found the teldir site has changed to the following: http://www.infobel.com/teldir/default.asp Maybe that's why their servers were always busy. Who knows. Anyway, IHTH you more. Best regards, Ron Pickard rpick...@hypercom.com Ron Pickard To: pat...@patton-assoc.com 01/29/2003 01:14 cc: emc-p...@majordomo.ieee.org, t...@world.std.com PM Subject: Re: Telephone Book for Iran(Document link: Ron Pickard) David, As for getting an actual Iranian telephone book, I'm afraid I cannot help you. However, you might want to try the following link. If you're not familiar with it, it provides telephone number/address search capabilities for essentially any country on the planet by linking to localized telephone company sites. Unfortunately, this site is currently experiencing technical difficulties, at present. But, when its working, it does work well. http://www.teldir.com/eng/ IHTH. Best regards, Ron Pickard rpick...@hypercom.com patton@patton-ass oc.com To: emc-p...@majordomo.ieee.org, t...@world.std.com Sent by: cc: treg-approval@worSubject: Telephone Book for Iran ld.std.com 01/29/2003 11:50 AM Please respond to patton Hello All: Would any one have a contact(s) with some any one that has an up to date Iranian Telephone book? We are seeking information (translated into English) which is generally contained in the first few pages of the telephone book, which identifies specific numbers for calling different types of services, such as the operator, international calling, Emergency Services, and others. Any name or contact or E Mail address information would be most sincerely appreciated. Best Regards David Patton Patton Associates 82 Wildwood Drive Prescott, Arizona 86305-5093 USA Tel: +1.928.771.2900 Fax: +1.928.771.2990 Toll Free: +1.877.311.8735 E Mail: pat...@patton-assoc.com Web: http://www.patton-assoc.com This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard:
Re: Unity Power Factor
Hi John: The only other problem that I know of is distribution transformer overheating. But, I believe such transformers are very much larger than 3 kVA, so 3 kVA of non-linear loads would have very little effect. I mean *concentrations* of loads, individually below 3 kVA or so. Distribution transformer overheating is the sort of effect that I am interested in. Are these MV/LV transformers, 'pole-pig' types or larger. Yes, delta-wye distribution transformer overheating does occur due to the circulation and dissipation of the triplen harmonics in the primary (delta) winding. As for the type of transformer, it is the first three- phase transformer upstream from a commercial or industrial load. (In North America, these transformers are relatively small compared to Euro practice.) Such transformers are usually a part of the (larger) customer premises wiring and installation, and are not a part of the public utility distribution system. So, harmonics in commercial/industrial equipment do not appear on the public network. In North America, this overheating problem due to triplen harmonics has largely disappeared with the advent of the distribution transformer K-factor rating that was developed especially for this problem. By contrast, homes in North America a supplied with single-phase from a single-phase distribution transformer (which is connected across two legs of a three-phase delta supply). So, harmonics in home equipment do not appear on the public network. (Each distribution transformer supplies a maximum of 8 homes, each with 200-amp service.) In addition to overheating neutrals, some manufacturers of partitions (for office cubes -- cube sweet cube!) included three-phase wiring. The neutral connection of partition-to-partition connectors tended to overheat due to harmonics, and several fires were reported. These, too, were fixed (I believe by doubling the neutral or the neutral connection). Best regards, Rich This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
power-line LAN
What are the unique testing requirements for a power-line based LAN (i.e. the information is transported on the powerlines within a home as an example) for CE mark? Would the power line harmonics be an issue? ANy unique set-up besides a couple of devices exchanging info? Hans Mellberg __ Do you Yahoo!? Yahoo! Mail Plus - Powerful. Affordable. Sign up now. http://mailplus.yahoo.com This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
RE: single fault conditions
Brian, I believe that forcing a FET failure would be a good test but should be in addition to the mechanical short method. If your power supply is safe for both failure modes that would be great. The fuse should open before the failed FET can cause a heat or fire problem. And it was already a shock hazard so that might not be an issue. The reason I would hesitate to use only the failed FET test is that changes in the type or manufacture or the FET could be an issue. And someone at UL might call you on not using the mechanical short test. If an actual failed component reveals a problem that the mechanical short does not, then the whole idea of a mechanical short test has a problem! Dave Cuthbert -Original Message- From: boconn...@t-yuden.com [mailto:boconn...@t-yuden.com] Sent: Wednesday, January 29, 2003 2:40 PM To: emc-p...@majordomo.ieee.org Subject: single fault conditions Good People of PSTC The environment being considered is a switching power supply. The technique that safety agencies use to simulate a SFC on a power FET does not seem, IMHO, to simulate the actual failure mode of the device. To wit: when the mosfet fails short, it blows itself open; so the amount of current sucked out of mains, e.g., the PFC FET, would probably open the component after a few input cycles. But if I apply a direct mechanical short (source to drain), current is being forced to flow until the fuse blows, or until some series trace or component opens. The Bad: some FETs fail very violently, and can actually be a fire hazard and/or shock hazard in open-frame switchers; but if the FET itself does not provide the short circuit, we will never know The Good: providing a continuous (mechanical) short will reveal if there are other components in the current path that could be cause the unit to fail in an unsafe mode. Although, according to QA records, these components have never failed, so it can be both demonstrated by design equations and empirical evidence that the SFC test does necessarily demonstrate anything relevant... The Ugly: Safety testing results in design corrections that do not increase product safety. So would it be legitimate to over-drive the gate, forcing short circuit current to flow through the FET, but not to apply a mechanical short across the component? Experiences comments are appreciated. R/S, Brian
RE: EN55022:1998 + A1:2000
Chris' Maxwell equations look correct. But the point at which ferrites are placed will not always have a common mode impedance of 50 ohms. Here's An example: a large DUT has a 1 meter long cable that connects to the ground plane. At 75 MHz the common mode impedance of the cable, at the DUT, is about 3k ohms. Adding a 1k +j1k ferrite at the DUT knocks down the radiation by 10 dB. But the radiation is not reduced mainly by losses but by detuning the antenna. The resonant frequency has shifted from 76 MHz to 60 MHz. Now 60 MHz could be a problem. I noticed this type of thing while trying ferrites to reduce emissions from a digital device that had a DUT cable (not grounded at the end). I could fix one frequency with ferrites but it would just tune the cable/system to resonance at another frequency. The person I was working with didn't believe this theory so I ADDED wire to the end of the DUT cable to make it 1/2 wavelength, rather than 1/4 wavelength at the offending frequency and dropped the signal by 20 dB. If anyone has any changes to the model or a what-if, I can simulate it and send you the simulated data. Dave Cuthbert Micron Technology From: Pettit, Ghery [mailto:ghery.pet...@intel.com] Sent: Wednesday, January 29, 2003 12:09 PM To: 'Chris Maxwell'; Pettit, Ghery; neve...@attbi.com; emc-p...@majordomo.ieee.org Subject: RE: EN55022:1998 + A1:2000 Chris, You can indeed make your own, but my bet is that A2LA or NIST NVLAP inspectors will want to see calibration data, not calculations. Now, if we just had a published calibration technique... Ghery From: Chris Maxwell [mailto:chris.maxw...@nettest.com] Sent: Wednesday, January 29, 2003 10:57 AM To: Pettit, Ghery; neve...@attbi.com; emc-p...@majordomo.ieee.org Subject: RE: EN55022:1998 + A1:2000 Ghery, If the standard is assuming a 50 Ohm system, doesn't this breakdown to a simple calculation? Insertion Loss = IL = 20 x log((50 + Zf) / 50)where Zf is the ferrite impedance This could easily be solved for Zf if you assume IL to be 15dB (in this case the dB are truely dimensionless; as you are calculating a pure loss from an arbitrary level). I would think that you would just have to: 1. Solve the above for Zf. By the way, I get 231.2 Ohms. Can someone check this? 2. Gather up a box of doughnuts such that the total Zf is above the answer for step 1 at all frequencies from 30Mhz to 1Ghz 3. Color code the doughnuts (or whatever) and write a procedure that says something like clamp three blue doughnuts and two red doughnuts over each cable ... Have I over simplified this??? Wouldn't this be proof enough for any accreditation body? I know that $300 may not seem like alot to some; but it adds up after a few cables. Besides; we went to college to learn all of that math; why not use some of it? I don't mind paying for stuff that I can't make; but this one seems possible to me. Chris Maxwell | Design Engineer - Optical Division email chris.maxw...@nettest.com | dir +1 315 266 5128 | fax +1 315 797 8024 NetTest | 6 Rhoads Drive, Utica, NY 13502 | USA web www.nettest.com | tel +1 315 797 4449 | -Original Message- From: Pettit, Ghery [SMTP:ghery.pet...@intel.com] Sent: Wednesday, January 29, 2003 11:59 AM To: 'neve...@attbi.com'; emc-p...@majordomo.ieee.org Subject: RE: EN55022:1998 + A1:2000 Amendment 1 to CISPR 22:1997 (Amendment A1:2000 to EN 55022:1998) requires that the clamps provide at least 15 dB of loss in a 50 ohm system over the frequency range of 30 MHz to 1000 MHz. The use of extension cords is prohibited. Can you guarantee that your bucket of doughnuts will meet this requirement? How will you demonstrate that to your lab's accrediting body? Fischer's clamps are around $300 each. Compared with what we had to choose from prior to their product, these are not big bucks. Ghery Pettit Intel This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron
RE: single fault conditions
Yes sir, this is another thing I've wondered about; i.e., simulating the big bus cap (short) SFC by applying a mechanical short accross the terminals. Does not really demonstrate what would occur if the cap itself fails. A blown electrolytic can be very messy. I am beginning to wonder about some of the testing that I perform that the agencies think is really great stuff... R/S, Brian From: Lou Aiken [mailto:ai...@gulftel.com] Sent: Wednesday, January 29, 2003 2:19 PM To: boconn...@t-yuden.com; emc-p...@majordomo.ieee.org Subject: Re: single fault conditions Wow, I would have to think a while about this. The first thing that comes to my mind, is the risk any greater than the bulk cap failure that spew debris around, and sometimes catch fire? There is no reasonable way to simulate that. Lou Aiken, LaMer LLC
RE: EN55022:1998 + A1:2000
The EM radiation from wires with and without ferrite cores can be simulated with NEC. The required parameters are: length of wire, physical orientation, how the end is terminated (floating? To ground?, frequency, the RL model of the ferrite). Then one can move the ferrite around to see what happens. There are situations where a single ferrite does virtually nothing. This why I am wary of just throwing on a ferrite and calling it good (although I have been known to do this). The complex impedance of a ferrite can be measured on a VNA. If a VNA isn't available an RF source, and a spectrum analyzer will give the scalar impedance. Or lately I have used a pulse generator and an oscilloscope to characterize ferrites for the design of wide-band time domain transmission line transformers. And I have used an MFJ-259B (only $260) to measure ferrites from 1.7 to 170 MHz. Dave Cuthbert Micron Technology From: Chris Maxwell [mailto:chris.maxw...@nettest.com] Sent: Wednesday, January 29, 2003 11:57 AM To: Pettit, Ghery; neve...@attbi.com; emc-p...@majordomo.ieee.org Subject: RE: EN55022:1998 + A1:2000 Ghery, If the standard is assuming a 50 Ohm system, doesn't this breakdown to a simple calculation? Insertion Loss = IL = 20 x log((50 + Zf) / 50)where Zf is the ferrite impedance This could easily be solved for Zf if you assume IL to be 15dB (in this case the dB are truely dimensionless; as you are calculating a pure loss from an arbitrary level). I would think that you would just have to: 1. Solve the above for Zf. By the way, I get 231.2 Ohms. Can someone check this? 2. Gather up a box of doughnuts such that the total Zf is above the answer for step 1 at all frequencies from 30Mhz to 1Ghz 3. Color code the doughnuts (or whatever) and write a procedure that says something like clamp three blue doughnuts and two red doughnuts over each cable ... Have I over simplified this??? Wouldn't this be proof enough for any accreditation body? I know that $300 may not seem like alot to some; but it adds up after a few cables. Besides; we went to college to learn all of that math; why not use some of it? I don't mind paying for stuff that I can't make; but this one seems possible to me. Chris Maxwell | Design Engineer - Optical Division email chris.maxw...@nettest.com | dir +1 315 266 5128 | fax +1 315 797 8024 NetTest | 6 Rhoads Drive, Utica, NY 13502 | USA web www.nettest.com | tel +1 315 797 4449 | -Original Message- From: Pettit, Ghery [SMTP:ghery.pet...@intel.com] Sent: Wednesday, January 29, 2003 11:59 AM To: 'neve...@attbi.com'; emc-p...@majordomo.ieee.org Subject: RE: EN55022:1998 + A1:2000 Amendment 1 to CISPR 22:1997 (Amendment A1:2000 to EN 55022:1998) requires that the clamps provide at least 15 dB of loss in a 50 ohm system over the frequency range of 30 MHz to 1000 MHz. The use of extension cords is prohibited. Can you guarantee that your bucket of doughnuts will meet this requirement? How will you demonstrate that to your lab's accrediting body? Fischer's clamps are around $300 each. Compared with what we had to choose from prior to their product, these are not big bucks. Ghery Pettit Intel This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
Re: single fault conditions
Wow, I would have to think a while about this. The first thing that comes to my mind, is the risk any greater than the bulk cap failure that spew debris around, and sometimes catch fire? There is no reasonable way to simulate that. Lou Aiken, LaMer LLC 27109 Palmetto Drive Orange Beach, AL 36561 USA tel ++ 1 251 981 6786 fax ++ 1 251 981 3054 Cell ++ 1 251 979 4648 - Original Message - From: boconn...@t-yuden.com To: emc-p...@majordomo.ieee.org Sent: Wednesday, January 29, 2003 3:40 PM Subject: single fault conditions Good People of PSTC The environment being considered is a switching power supply. The technique that safety agencies use to simulate a SFC on a power FET does not seem, IMHO, to simulate the actual failure mode of the device. To wit: when the mosfet fails short, it blows itself open; so the amount of current sucked out of mains, e.g., the PFC FET, would probably open the component after a few input cycles. But if I apply a direct mechanical short (source to drain), current is being forced to flow until the fuse blows, or until some series trace or component opens. The Bad: some FETs fail very violently, and can actually be a fire hazard and/or shock hazard in open-frame switchers; but if the FET itself does not provide the short circuit, we will never know The Good: providing a continuous (mechanical) short will reveal if there are other components in the current path that could be cause the unit to fail in an unsafe mode. Although, according to QA records, these components have never failed, so it can be both demonstrated by design equations and empirical evidence that the SFC test does necessarily demonstrate anything relevant... The Ugly: Safety testing results in design corrections that do not increase product safety. So would it be legitimate to over-drive the gate, forcing short circuit current to flow through the FET, but not to apply a mechanical short across the component? Experiences comments are appreciated. R/S, Brian
RE: EN55022:1998 + A1:2000
I believe that selecting the right combination of ferrites once, by testing them to provide at least 15 dB S21 should do it. Then it should be a matter of keeping it documented and used in a test-procedure, to ensure that every time one uses the same arrangement. Regrading the proposal that it must provide at least 15 dB attenuation AND 150 Ohm input impedance at the same time, that sounds somewhat trickier. Neven Chris, You can indeed make your own, but my bet is that A2LA or NIST NVLAP inspectors will want to see calibration data, not calculations. Now, if we just had a published calibration technique... Ghery -Original Message- From: Chris Maxwell [mailto:chris.maxw...@nettest.com] Sent: Wednesday, January 29, 2003 10:57 AM To: Pettit, Ghery; neve...@attbi.com; emc-p...@majordomo.ieee.org Subject: RE: EN55022:1998 + A1:2000 Ghery, If the standard is assuming a 50 Ohm system, doesn't this breakdown to a simple calculation? Insertion Loss = IL = 20 x log((50 + Zf) / 50)where Zf is the ferrite impedance This could easily be solved for Zf if you assume IL to be 15dB (in this case the dB are truely dimensionless; as you are calculating a pure loss from an arbitrary level). I would think that you would just have to: 1. Solve the above for Zf. By the way, I get 231.2 Ohms. Can someone check this? 2. Gather up a box of doughnuts such that the total Zf is above the answer for step 1 at all frequencies from 30Mhz to 1Ghz 3. Color code the doughnuts (or whatever) and write a procedure that says something like clamp three blue doughnuts and two red doughnuts over each cable ... Have I over simplified this??? Wouldn't this be proof enough for any accreditation body? I know that $300 may not seem like alot to some; but it adds up after a few cables. Besides; we went to college to learn all of that math; why not use some of it? I don't mind paying for stuff that I can't make; but this one seems possible to me. Chris Maxwell | Design Engineer - Optical Division email chris.maxw...@nettest.com | dir +1 315 266 5128 | fax +1 315 797 8024 NetTest | 6 Rhoads Drive, Utica, NY 13502 | USA web www.nettest.com | tel +1 315 797 4449 | -Original Message- From: Pettit, Ghery [SMTP:ghery.pet...@intel.com] Sent: Wednesday, January 29, 2003 11:59 AM To: 'neve...@attbi.com'; emc-p...@majordomo.ieee.org Subject:RE: EN55022:1998 + A1:2000 Amendment 1 to CISPR 22:1997 (Amendment A1:2000 to EN 55022:1998) requires that the clamps provide at least 15 dB of loss in a 50 ohm system over the frequency range of 30 MHz to 1000 MHz. The use of extension cords is prohibited. Can you guarantee that your bucket of doughnuts will meet this requirement? How will you demonstrate that to your lab's accrediting body? Fischer's clamps are around $300 each. Compared with what we had to choose from prior to their product, these are not big bucks. Ghery Pettit Intel --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
Re: Unity Power Factor
I haven't been following this thread closely, so if the following has already been addressed, I apologize. I noticed this several years ago at the office building I worked in at the time. My cube moved from one end of the building to another, and my computer wouldn't always start - it took several tries. I brought in a scope, and saw that the ac voltage waveform was flattened. It was more flattened at my new cube than at my old one. Clearly this is related to power supplies recharging filter caps at the peak of the ac waveform, and the relative distance from the building main breaker at the two different cubes. This is a power/crest factor issue, not directly a harmonic issue, although drawing current only near the peak of the waveform will definitely generate harmonics. From: John Woodgate j...@jmwa.demon.co.uk To: emc-p...@majordomo.ieee.org Subject: Re: Unity Power Factor Date: Wed, Jan 29, 2003, 2:23 PM I read in !emc-pstc that Rich Nute ri...@sdd.hp.com wrote (in 200301291623.iaa07...@epgc264.sdd.hp.com) about 'Unity Power Factor' on Wed, 29 Jan 2003: Hi John: In the USA, this has largely been fixed by a change in the USA National Electrical Code. There must be quite a number of installations that are not yet upgraded. Where a problem existed, it was fixed by pulling another neutral. Yes, we do that, too. Are there any other problems appearing in the field which can be reliably determined as due to concentrations of non-linear loads of less than 3 kVA or so? Probably not. The only other problem that I know of is distribution transformer overheating. But, I believe such transformers are very much larger than 3 kVA, so 3 kVA of non-linear loads would have very little effect. I mean *concentrations* of loads, individually below 3 kVA or so. Distribution transformer overheating is the sort of effect that I am interested in. Are these MV/LV transformers, 'pole-pig' types or larger. -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk Interested in professional sound reinforcement and distribution? Then go to http://www.isce.org.uk PLEASE do NOT copy news posts to me by E-MAIL! --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
Re: EN55022:1998 + A1:2000
I read in !emc-pstc that Chris Maxwell chris.maxw...@nettest.com wrote (in 83d652574e7af740873674f9fc12dbaaf7e...@utexh1w2.gnnettest.com) about 'EN55022:1998 + A1:2000' on Wed, 29 Jan 2003: If the standard is assuming a 50 Ohm system, doesn't this breakdown to a simple calculation? Quite possibly, but it *isn't* a 50 ohm system. The device should absorb the energy passing down the cable, not reflect it, so it should match the impedance of the cable/ground propagator well. This propagator has traditionally been assumed to have a characteristic impedance of 150 ohms. In an earlier post, I said that the transfer attenuation is 'irrelevant', and it escaped before I could correct it. It wouldn't be irrelevant if it were 3 dB, say, because that would mean that only half the energy was absorbed. So, it would be fairer to say that the attenuation is 'of secondary importance' compared with the input impedance, because if the impedance is far out, the energy never gets into the device, so can't be absorbed. -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk Interested in professional sound reinforcement and distribution? Then go to http://www.isce.org.uk PLEASE do NOT copy news posts to me by E-MAIL! This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
Re: Declaration of Conformity
I read in !emc-pstc that Scott Douglas dougl...@naradnetworks.com wrote (in 5.0.2.1.2.20030129141347.00a63...@pop.business.earthlink.net ) about 'Declaration of Conformity' on Wed, 29 Jan 2003: Please forgive my mental lapse here. I know this subject has come up before. This is a question of what to do with the Declaration of Conformity for the EU. So please tell me what you do. Do you put a CE mark on the outside of the box? It's a good idea to do so; it keeps the Customs fingers out of the box. Is this in lieu of the D of C? Absolutely not. Do you put the D of C on the outside of the box? Not normally. I see no reason to do so. Do you put the D of C inside the box on separate paper? If you want to, or print it in the instruction book. Most safety standards *require* an instruction book to be provided. Do you put the D of C in (on) a CD ROM and no paper in the box? It's a few lines of text. Why would you put it on a CD-ROM? Do you include the D of C with Customs papers only? It is highly advisable to include it with shipping documents, but 'only' is too definite. -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk Interested in professional sound reinforcement and distribution? Then go to http://www.isce.org.uk PLEASE do NOT copy news posts to me by E-MAIL! This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
Re: RTTE directive.
I read in !emc-pstc that Gary McInturff Gary.McInturff@worldwidepackets .com wrote (in 4e9a9436c008314eaa32033b23e96fd90b0...@thorondor.wwp.co m) about 'RTTE directive.' on Wed, 29 Jan 2003: Anybody have a link to peruse and purchase this, and a brief synopsis. Replied to a previous e-mail question, by e-mail. -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk Interested in professional sound reinforcement and distribution? Then go to http://www.isce.org.uk PLEASE do NOT copy news posts to me by E-MAIL! This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
single fault conditions
Good People of PSTC The environment being considered is a switching power supply. The technique that safety agencies use to simulate a SFC on a power FET does not seem, IMHO, to simulate the actual failure mode of the device. To wit: when the mosfet fails short, it blows itself open; so the amount of current sucked out of mains, e.g., the PFC FET, would probably open the component after a few input cycles. But if I apply a direct mechanical short (source to drain), current is being forced to flow until the fuse blows, or until some series trace or component opens. The Bad: some FETs fail very violently, and can actually be a fire hazard and/or shock hazard in open-frame switchers; but if the FET itself does not provide the short circuit, we will never know The Good: providing a continuous (mechanical) short will reveal if there are other components in the current path that could be cause the unit to fail in an unsafe mode. Although, according to QA records, these components have never failed, so it can be both demonstrated by design equations and empirical evidence that the SFC test does necessarily demonstrate anything relevant... The Ugly: Safety testing results in design corrections that do not increase product safety. So would it be legitimate to over-drive the gate, forcing short circuit current to flow through the FET, but not to apply a mechanical short across the component? Experiences comments are appreciated. R/S, Brian
Re: EN55022:1998 + A1:2000
I read in !emc-pstc that Gert Gremmen g.grem...@cetest.nl wrote (in mpeeiccjhhndekobpnnbmeegckaa.g.grem...@cetest.nl) about 'EN55022:1998 + A1:2000' on Wed, 29 Jan 2003: Proposals are on their way to specify both transfer attenuation (first) and input CM impedance of those clamps (later) The radiation properties of the exposed wire will vary widely depending on the CM load impedance. The attenuation characteristic is to isolate auxilary wire (and signal) from the test setup. When we discussed this in the UK committee, it was pointed out that this clamp is NOT a filter and its transfer attenuation is irrelevant. It is *intended* to absorb energy propagating down the cable, so it is the *input impedance* that matters. AIUI, even though that is so, because CISPR/I (G?) specified a transfer attenuation, CISPR 16-1 will continue to specify a value for this irrelevant property! -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk Interested in professional sound reinforcement and distribution? Then go to http://www.isce.org.uk PLEASE do NOT copy news posts to me by E-MAIL! This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
EN61000-3-2/3 applicability
The scope of these standards includes all equipment having an input current upto and including 16A per phase and intended to be connected to a public low-voltage distribution systems of between 220V and 250V at 50Hz line to neutral. Does public infer that only consumer goods that use residential service are obligated to these standards or are industrial products used in industrial locations that meet the electrical specifications as identified above also obligated to these standards? Kind Regards, Sam Wismer Engineering Manager ACS, Inc. *Tel: (770) 831-8048 *Fax: (770) 831-8598 *Web: http://www.acstestlab.com www.acstestlab.com mailto:*swis...@acstestlab.com *swis...@acstestlab.com
RE: EN55022:1998 + A1:2000
Ghery Pettit wrote: Chris, You can indeed make your own, but my bet is that A2LA or NIST NVLAP inspectors will want to see calibration data, not calculations. Now, if we just had a published calibration technique... This is still not rocket science. Using Z = 138*(log OD/ID) --- for an air dielectric -- a 2.3:1 ratio of inner conductor diameter to outer conductor's inner diameter gives a 50 ohm fixture. A fixture with this impedance may be constructed which will allow slipping beads on the center conductor and _measuring_ the resulting attenuation. The instruments we measure with ARE traceably calibrated to a primary standard. And since the attenuation requirement is a _minimum_, not a precise value, it is quite easy to insure that it is met. Cortland This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
RE: EN55022:1998 + A1:2000
Indeed, a very good point! I wonder what is meant by the 50 Ohm system does that mean a function generator with 50 Ohm output impedance, 50 Ohm cable and a 50 Ohm load? (This could be simulated nicely by connecting a function generator to a 50 Ohm spectrum analyzer input using 50 Ohm cable) If that were the case, then calibration would be relatively easy. If that were the case, then my initial calculation would also have to be adjusted to take into account the total non-ferrite impedance which would be closer to 150 Ohms...Yielding a calculated Zf of 693 Ohms. I previously assumed that a 50Ohm system had a total pre-ferrite impedance of 50 Ohms, which gave me a Zf of 231 Ohms. Of course, the standard says 15dB minimum... so you could just use 1000 Ohms (at all frequencies, remember) and be done with it! It probably still wouldn't cost $300. Before anybody goes out and buys ferrites ala carte, remember; I'm not on any CISPR commitees; I'm just throwing out a little bit of Math and some assumptions and suggesting that this could be done. Chris Maxwell | Design Engineer - Optical Division email chris.maxw...@nettest.com | dir +1 315 266 5128 | fax +1 315 797 8024 NetTest | 6 Rhoads Drive, Utica, NY 13502 | USA web www.nettest.com | tel +1 315 797 4449 | -Original Message- From: Pettit, Ghery [SMTP:ghery.pet...@intel.com] Sent: Wednesday, January 29, 2003 2:09 PM To: Chris Maxwell; Pettit, Ghery; neve...@attbi.com; emc-p...@majordomo.ieee.org Subject: RE: EN55022:1998 + A1:2000 Chris, You can indeed make your own, but my bet is that A2LA or NIST NVLAP inspectors will want to see calibration data, not calculations. Now, if we just had a published calibration technique... Ghery This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
Re: Unity Power Factor
I read in !emc-pstc that Rich Nute ri...@sdd.hp.com wrote (in 200301291623.iaa07...@epgc264.sdd.hp.com) about 'Unity Power Factor' on Wed, 29 Jan 2003: Hi John: In the USA, this has largely been fixed by a change in the USA National Electrical Code. There must be quite a number of installations that are not yet upgraded. Where a problem existed, it was fixed by pulling another neutral. Yes, we do that, too. Are there any other problems appearing in the field which can be reliably determined as due to concentrations of non-linear loads of less than 3 kVA or so? Probably not. The only other problem that I know of is distribution transformer overheating. But, I believe such transformers are very much larger than 3 kVA, so 3 kVA of non-linear loads would have very little effect. I mean *concentrations* of loads, individually below 3 kVA or so. Distribution transformer overheating is the sort of effect that I am interested in. Are these MV/LV transformers, 'pole-pig' types or larger. -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk Interested in professional sound reinforcement and distribution? Then go to http://www.isce.org.uk PLEASE do NOT copy news posts to me by E-MAIL! This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
Re: Telephone Book for Iran
David, As for getting an actual Iranian telephone book, I'm afraid I cannot help you. However, you might want to try the following link. If you're not familiar with it, it provides telephone number/address search capabilities for essentially any country on the planet by linking to localized telephone company sites. Unfortunately, this site is currently experiencing technical difficulties, at present. But, when its working, it does work well. http://www.teldir.com/eng/ IHTH. Best regards, Ron Pickard rpick...@hypercom.com patton@patton-ass oc.com To: emc-p...@majordomo.ieee.org, t...@world.std.com Sent by: cc: treg-approval@worSubject: Telephone Book for Iran ld.std.com 01/29/2003 11:50 AM Please respond to patton Hello All: Would any one have a contact(s) with some any one that has an up to date Iranian Telephone book? We are seeking information (translated into English) which is generally contained in the first few pages of the telephone book, which identifies specific numbers for calling different types of services, such as the operator, international calling, Emergency Services, and others. Any name or contact or E Mail address information would be most sincerely appreciated. Best Regards David Patton Patton Associates 82 Wildwood Drive Prescott, Arizona 86305-5093 USA Tel: +1.928.771.2900 Fax: +1.928.771.2990 Toll Free: +1.877.311.8735 E Mail: pat...@patton-assoc.com Web: http://www.patton-assoc.com This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
Associated Research Model 6554SA Compliance Analyzer for sale
For anyone looking for a very useful piece of Product Safety test gear, you can’t beat Associated Research’s line of automated Compliance Analyzers. I have an extra one and am offering it for sale on eBay: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItemitem=3309216981 item=3309216981 Best regards, Dave 512.695.5871 www.lorusso.com http://www.lorusso.com/
RE: Automotive v. EMC Directives
You're right that the link I gave only gets you a copy of the Directive without the figures. The only downloadable versions I've found that do have the figures are the .tif format ones available if you search on the document from the following location: http://europa.eu.int/eur-lex/en/search/search_lif.html The search results will offer you the option of having a .tif file e-mailed to you. There are drawbacks to this - slow fuzzy viewing and large file size which resulted in them breaking the directive into 2 parts when they sent it to me. Does anyone know another way to get directives on-line complete with the figures, without resorting to .tif files? Thanks, Jim Eichner, P.Eng. Regulatory Compliance Manager Xantrex Technology Inc. phone: (604) 422-2546 fax: (604) 420-1591 e-mail: jim.eich...@xantrex.com web: www.xantrex.com Confidentiality Notice: This email message, including any attachments, is for the sole use of the intended recipient(s) and may contain confidential and privileged information. Any unauthorized review, use, disclosure or distribution is prohibited. If you are not the intended recipient, please contact the sender by reply e-mail and destroy all copies of the original message. From: KC CHAN [PDD] [mailto:kcc...@hkpc.org] Sent: Tuesday, January 28, 2003 7:40 PM To: alan.hud...@amsjv.com; emc-p...@majordomo.ieee.org; jim.eich...@xantrex.com Subject: RE: Automotive v. EMC Directives Where can I have the figures referenced in the link? Jim Eichner jim.eich...@xantrex.com 01/29/03 03:46am The requirements are very different, especially in the test setup, and I don't think you can make assumptions in either direction. For an electronic sub-assembly, for example, you do radiated emissions at a measurement distance of 1m, which is very much in the near field. You won't likely be able to make any assumptions from that as to how you will fare in a 3m or 10m emissions test for the EMC Directive, which is arguably in the far field. There are lots of other significant differences, so I'm afraid you'll need to do the reading and do some testing. One bit of good news: the Automotive EMC Directive contains its own requirements, so you don't need to buy standards to go along with it. Here's a link: http://europa.eu.int/smartapi/cgi/sga_doc?smartapi!celexapi!prod!CELEXnumdoc lg=ENnumdoc=31995L0054model=guichett Good luck, Jim Eichner, P.Eng. Regulatory Compliance Manager Xantrex Technology Inc. e-mail: jim.eich...@xantrex.com web: www.xantrex.com Any opinions expressed are those of my invisible friend, who really exists. Honest. No really. Confidentiality Notice: This email message, including any attachments, is for the sole use of the intended recipient(s) and may contain confidential and privileged information. Any unauthorized review, use, disclosure or distribution is prohibited. If you are not the intended recipient, please contact the sender by reply e-mail and destroy all copies of the original message. From: Hudson, Alan [mailto:alan.hud...@amsjv.com] Sent: Tuesday, January 28, 2003 9:34 AM To: EMC-pstc (E-mail) Subject: Automotive v. EMC Directives G'Day! Is anyone familiar with the standards needed to comply with the Automotive *and* the EMC Directives? How do they compare? Or to put it another way, if an item of equipment was known to be compliant with the Automotive Directive, is it likely that it would therefore meet the requirements of the EMC Directive? Alan -- Alenia Marconi Systems Scotland This email and any attachments are confidential to the intended recipient and may also be privileged. If you are not the intended recipient please delete it from your system and notify the sender. You should not copy it or use it for any purpose nor disclose or distribute its contents to any other person. This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For
Telephone Book for Iran
Hello All: Would any one have a contact(s) with some any one that has an up to date Iranian Telephone book? We are seeking information (translated into English) which is generally contained in the first few pages of the telephone book, which identifies specific numbers for calling different types of services, such as the operator, international calling, Emergency Services, and others. Any name or contact or E Mail address information would be most sincerely appreciated. Best Regards David Patton Patton Associates 82 Wildwood Drive Prescott, Arizona 86305-5093 USA Tel: +1.928.771.2900 Fax: +1.928.771.2990 Toll Free: +1.877.311.8735 E Mail: pat...@patton-assoc.com Web: http://www.patton-assoc.com This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
Declaration of Conformity
Hi Ya'll, Please forgive my mental lapse here. I know this subject has come up before. This is a question of what to do with the Declaration of Conformity for the EU. So please tell me what you do. Do you put a CE mark on the outside of the box? Is this in lieu of the D of C? Do you put the D of C on the outside of the box? Do you put the D of C inside the box on separate paper? Do you put the D of C in (on) a CD ROM and no paper in the box? Do you include the D of C with Customs papers only? So as to not clutter the list, off-list replies would be preferred. Thanks in advance for you replies. Scott Douglas Senior Compliance Engineer Narad Networks 515 Groton Road Westford, MA 01886 phone: 978 589-1869 dougl...@naradnetworks.com www.naradnetworks.com http://www.naradnetworks.com/ --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
RE: EN55022:1998 + A1:2000
Chris, You can indeed make your own, but my bet is that A2LA or NIST NVLAP inspectors will want to see calibration data, not calculations. Now, if we just had a published calibration technique... Ghery From: Chris Maxwell [mailto:chris.maxw...@nettest.com] Sent: Wednesday, January 29, 2003 10:57 AM To: Pettit, Ghery; neve...@attbi.com; emc-p...@majordomo.ieee.org Subject: RE: EN55022:1998 + A1:2000 Ghery, If the standard is assuming a 50 Ohm system, doesn't this breakdown to a simple calculation? Insertion Loss = IL = 20 x log((50 + Zf) / 50)where Zf is the ferrite impedance This could easily be solved for Zf if you assume IL to be 15dB (in this case the dB are truely dimensionless; as you are calculating a pure loss from an arbitrary level). I would think that you would just have to: 1. Solve the above for Zf. By the way, I get 231.2 Ohms. Can someone check this? 2. Gather up a box of doughnuts such that the total Zf is above the answer for step 1 at all frequencies from 30Mhz to 1Ghz 3. Color code the doughnuts (or whatever) and write a procedure that says something like clamp three blue doughnuts and two red doughnuts over each cable ... Have I over simplified this??? Wouldn't this be proof enough for any accreditation body? I know that $300 may not seem like alot to some; but it adds up after a few cables. Besides; we went to college to learn all of that math; why not use some of it? I don't mind paying for stuff that I can't make; but this one seems possible to me. Chris Maxwell | Design Engineer - Optical Division email chris.maxw...@nettest.com | dir +1 315 266 5128 | fax +1 315 797 8024 NetTest | 6 Rhoads Drive, Utica, NY 13502 | USA web www.nettest.com | tel +1 315 797 4449 | -Original Message- From: Pettit, Ghery [SMTP:ghery.pet...@intel.com] Sent: Wednesday, January 29, 2003 11:59 AM To: 'neve...@attbi.com'; emc-p...@majordomo.ieee.org Subject: RE: EN55022:1998 + A1:2000 Amendment 1 to CISPR 22:1997 (Amendment A1:2000 to EN 55022:1998) requires that the clamps provide at least 15 dB of loss in a 50 ohm system over the frequency range of 30 MHz to 1000 MHz. The use of extension cords is prohibited. Can you guarantee that your bucket of doughnuts will meet this requirement? How will you demonstrate that to your lab's accrediting body? Fischer's clamps are around $300 each. Compared with what we had to choose from prior to their product, these are not big bucks. Ghery Pettit Intel This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
RE: EN55022:1998 + A1:2000
Ghery, If the standard is assuming a 50 Ohm system, doesn't this breakdown to a simple calculation? Insertion Loss = IL = 20 x log((50 + Zf) / 50)where Zf is the ferrite impedance This could easily be solved for Zf if you assume IL to be 15dB (in this case the dB are truely dimensionless; as you are calculating a pure loss from an arbitrary level). I would think that you would just have to: 1. Solve the above for Zf. By the way, I get 231.2 Ohms. Can someone check this? 2. Gather up a box of doughnuts such that the total Zf is above the answer for step 1 at all frequencies from 30Mhz to 1Ghz 3. Color code the doughnuts (or whatever) and write a procedure that says something like clamp three blue doughnuts and two red doughnuts over each cable ... Have I over simplified this??? Wouldn't this be proof enough for any accreditation body? I know that $300 may not seem like alot to some; but it adds up after a few cables. Besides; we went to college to learn all of that math; why not use some of it? I don't mind paying for stuff that I can't make; but this one seems possible to me. Chris Maxwell | Design Engineer - Optical Division email chris.maxw...@nettest.com | dir +1 315 266 5128 | fax +1 315 797 8024 NetTest | 6 Rhoads Drive, Utica, NY 13502 | USA web www.nettest.com | tel +1 315 797 4449 | -Original Message- From: Pettit, Ghery [SMTP:ghery.pet...@intel.com] Sent: Wednesday, January 29, 2003 11:59 AM To: 'neve...@attbi.com'; emc-p...@majordomo.ieee.org Subject: RE: EN55022:1998 + A1:2000 Amendment 1 to CISPR 22:1997 (Amendment A1:2000 to EN 55022:1998) requires that the clamps provide at least 15 dB of loss in a 50 ohm system over the frequency range of 30 MHz to 1000 MHz. The use of extension cords is prohibited. Can you guarantee that your bucket of doughnuts will meet this requirement? How will you demonstrate that to your lab's accrediting body? Fischer's clamps are around $300 each. Compared with what we had to choose from prior to their product, these are not big bucks. Ghery Pettit Intel This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
RE: RTTE directive.
Hope the following links help - I think it is what you are looking for : Link to the text of the RTTE Directive : http://europa.eu.int/comm/enterprise/rtte/dir99-5.htm List of harmonised standards published in the Official Journal of the EC for the RTTE: http://europa.eu.int/eur-lex/en/dat/2002/c_304/c_30420021207en00160042.pdf General RTTE information : http://europa.eu.int/comm/enterprise/rtte/infor.htm Mark Render EMC and Radio Group Manager KTL Saxon Way Priory Park West Hessle East Yorkshire HU13 9PB From: Gary McInturff [mailto:gary.mcintu...@worldwidepackets.com] Sent: 29 January 2003 16:11 To: EMC-PSTC (E-mail) Subject: RTTE directive. Anybody have a link to peruse and purchase this, and a brief synopsis. I assume it calls out the standard EMC tests - EN55022, EN55024, and Safety standards, along with a standard or section which deals with the intentional radiator portion of box, and harmonized frequencies etc. The device itself is a Wi-fi type box. Ethernet in, and RF out. Is that correct? Gary This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
RE: EN55022:1998 + A1:2000
Gert et al Can anyone provide a spec for the ferrite. For example, what is typically used in a CISPR 16 radiated power clamp? I am guessing when I say that I believe these were originally a Philips type ferrite ring. I have two of these clamps (Luthi MDS21 and Anritsu) and have found them to be quite different in terms of attenuation characteristics when used as loads in 61000-4-6 conducted immunity testing. A short tutorial on the characteristics of ferrites as used in these clamps would be nice. Is anyone aware of a source, eg in a particular standard? Best Regards John Cronin From: Gert Gremmen Reply-To: Gert Gremmen To: Gordon,Ian , Subject: RE: EN55022:1998 + A1:2000 Date: Wed, 29 Jan 2003 16:54:00 +0100 Hi Group, Proposals are on their way to specify both transfer attenuation (first) and input CM impedance of those clamps (later) The radiation properties of the exposed wire will vary widely depending on the CM load impedance. The attenuation characteristic is to isolate auxilary wire (and signal) from the test setup. Both will be published as an Amendment on CISPR 16 document. A controllable impedance clamp system can be constructed using a current clamp system with variable load . (like current clamp/transformer) The first 1-5 rings can be loaded with a screened wire that terminates into a variable ( or fixed) impedance. Target CM impedance will probably be 150 Ohm to be transferred to the load. This has best impact in the lower frequency range. High loss ferrite will do better as low loss ferrite. Attenuation is just a matter of quantity of rings. Regards, Gert Gremmen Manager Ce-test, Qualified Testing ce marking and more .. EMCD LVD RTTED MDD MD www.cetest.nl Electrical / Electronic Equipment -Original Message- From: owner-emc-p...@majordomo.ieee.org [mailto:owner-emc-p...@majordomo.ieee.org]On Behalf Of Gordon,Ian Sent: Wednesday, January 29, 2003 11:51 AM To: emc-p...@majordomo.ieee.org Subject: RE: EN55022:1998 + A1:2000 All I can see that my manager would prefer to use Neven's approach - it is probably much cheaper than buying clamps. However, does anybody have any practical experience of this? A reply from an accredited test house would be welcomed! Thanks Ian Gordon -Original Message- From: neve...@attbi.com [mailto:neve...@attbi.com] Sent: 29 January 2003 05:22 To: emc-p...@majordomo.ieee.org Subject: Re: EN55022:1998 + A1:2000 Instead of paying big bucks for the clamps (I am not sure what the price is, but I'm sure it is too much anyway :), why not buying a bucket of ferrite doughnuts that can be used over cables. Or, when possible, building in-line adapters out of sections of cables (maybe 1m long) and lining them up with ferrites. I'd select a combination of ferrites to cover 30 MHz to about 300 MHz. The high frequencies will be radiated anyway by the segment of the cables close to the DUT. Taking a little more thorough approach, I'd check the impedance with the lineup fixed over a defined height above a GND plane. (Not sure if that would make a big practical difference.) Neven A1 to EN55022:1998 requires the use of ferrite clamps on all cables leaving the table-top EUT for a connection outside the test site. Are there any other manufacturers of these clamps other than Fischer Custom Communications? Richard Woods Sensormatic Electronics Tyco International _ This e-mail has been scanned for viruses by the WorldCom Internet Managed Scanning Service - powered by MessageLabs. For further information visit http://www.worldcom.com --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute:
RE: EN55022:1998 + A1:2000
Hi Group, Proposals are on their way to specify both transfer attenuation (first) and input CM impedance of those clamps (later) The radiation properties of the exposed wire will vary widely depending on the CM load impedance. The attenuation characteristic is to isolate auxilary wire (and signal) from the test setup. Both will be published as an Amendment on CISPR 16 document. A controllable impedance clamp system can be constructed using a current clamp system with variable load . (like current clamp/transformer) The first 1-5 rings can be loaded with a screened wire that terminates into a variable ( or fixed) impedance. Target CM impedance will probably be 150 Ohm to be transferred to the load. This has best impact in the lower frequency range. High loss ferrite will do better as low loss ferrite. Attenuation is just a matter of quantity of rings. Regards, Gert Gremmen Manager Ce-test, Qualified Testing ce marking and more .. EMCD LVD RTTED MDD MD www.cetest.nl Electrical / Electronic Equipment From: owner-emc-p...@majordomo.ieee.org [mailto:owner-emc-p...@majordomo.ieee.org]On Behalf Of Gordon,Ian Sent: Wednesday, January 29, 2003 11:51 AM To: emc-p...@majordomo.ieee.org Subject: RE: EN55022:1998 + A1:2000 All I can see that my manager would prefer to use Neven's approach - it is probably much cheaper than buying clamps. However, does anybody have any practical experience of this? A reply from an accredited test house would be welcomed! Thanks Ian Gordon From: neve...@attbi.com [mailto:neve...@attbi.com] Sent: 29 January 2003 05:22 To: emc-p...@majordomo.ieee.org Subject: Re: EN55022:1998 + A1:2000 Instead of paying big bucks for the clamps (I am not sure what the price is, but I'm sure it is too much anyway :), why not buying a bucket of ferrite doughnuts that can be used over cables. Or, when possible, building in-line adapters out of sections of cables (maybe 1m long) and lining them up with ferrites. I'd select a combination of ferrites to cover 30 MHz to about 300 MHz. The high frequencies will be radiated anyway by the segment of the cables close to the DUT. Taking a little more thorough approach, I'd check the impedance with the lineup fixed over a defined height above a GND plane. (Not sure if that would make a big practical difference.) Neven A1 to EN55022:1998 requires the use of ferrite clamps on all cables leaving the table-top EUT for a connection outside the test site. Are there any other manufacturers of these clamps other than Fischer Custom Communications? Richard Woods Sensormatic Electronics Tyco International _ This e-mail has been scanned for viruses by the WorldCom Internet Managed Scanning Service - powered by MessageLabs. For further information visit http://www.worldcom.com This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
RE: EN55022:1998 + A1:2000
Amendment 1 to CISPR 22:1997 (Amendment A1:2000 to EN 55022:1998) requires that the clamps provide at least 15 dB of loss in a 50 ohm system over the frequency range of 30 MHz to 1000 MHz. The use of extension cords is prohibited. Can you guarantee that your bucket of doughnuts will meet this requirement? How will you demonstrate that to your lab's accrediting body? Fischer's clamps are around $300 each. Compared with what we had to choose from prior to their product, these are not big bucks. Ghery Pettit Intel From: neve...@attbi.com [mailto:neve...@attbi.com] Sent: Tuesday, January 28, 2003 9:22 PM To: emc-p...@majordomo.ieee.org Subject: Re: EN55022:1998 + A1:2000 Instead of paying big bucks for the clamps (I am not sure what the price is, but I'm sure it is too much anyway :), why not buying a bucket of ferrite doughnuts that can be used over cables. Or, when possible, building in-line adapters out of sections of cables (maybe 1m long) and lining them up with ferrites. I'd select a combination of ferrites to cover 30 MHz to about 300 MHz. The high frequencies will be radiated anyway by the segment of the cables close to the DUT. Taking a little more thorough approach, I'd check the impedance with the lineup fixed over a defined height above a GND plane. (Not sure if that would make a big practical difference.) Neven A1 to EN55022:1998 requires the use of ferrite clamps on all cables leaving the table-top EUT for a connection outside the test site. Are there any other manufacturers of these clamps other than Fischer Custom Communications? Richard Woods Sensormatic Electronics Tyco International --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
RE: Circuit Breaker Tripping Dring Fault Tests
From: Gregg Kervill Sent: Tuesday, January 28, 2003 3:21 PM Like most regulatory issues the answer is YES and NO. Therefore it is dangerous and extremely misleading (to many lurkers) to apply a general answer to all conditions: Generally the equipment is expected to protect itself with internal over current and short-circuit protection. I disagree. It may be possible for equipment to possess inherent features that do not require supplementary protection or that a piece of equipment is adequately protected by the branch circuit protection. Much depends on the application and design. The equipment will be tested with the worst case fault condition – 60 kAmp or more is not uncommon This value may be true for equipment installed in Category IV and possibly Category III environments (per IEC60664-1), but is neither the general case nor very common for equipment installed in Category II environments. Consider that every finite (though minute) impedance at every electrical connection will serve to limit the fault current available at equipment. Impedances will also exist at each switchable contact (molded case switches and circuit breakers) and each wiping contact (fuse holders for replaceable cartridge fuses, outlets/plugs, knife switches). For North America: In a typical household operating at 120V, it's unlikely that a fault current available to Pluggable Equipment Type A will be much above 5kA, even if the outlet supplying the equipment is within 5 ft. of the service entrance. In a typical household operating at 240V, the available fault current will be somewhat higher (approximately doubled +). This is also, in large measure, due to the relatively small last distribution transformer before the household and other loads on the transformer from other households supplied by the same transformer. In a typical business the fault current available will be larger, due largely to a larger transformer connected to the service entrance and that the service entrance voltages are greater (480V three phase is not uncommon for larger facilities; 120/208V is most common). I'm not certain of the typical fault currents available at an outlet in this case, but I'd venture a guess that its not more than 25kA at a ANSI/NEMA 5-15 outlet. I'm interested in hearing typical values for other regions of the world, so if anyone has any data or reasonable guesses, please let us all know. Where we rely upon the ‘breaker’ for - non-domestic equipment - it is ALWAYS mandatory (and common sense) to specify the characteristics of that breaker in terms of ‘tripping (operating) current’ – time characteristics (Type I, II or III) and Breaking Current 2,500 Amps is low for most domestic situations. This must be for Europe. In the US (and I believe Canada is the same), 5kA is a gimme interrupting rating for molded case switches and circuit breakers. The minimum interrupting rating for branch circuit fuses is 10kA. A failure to provide the necessary information WILL eventually result in a fire or nuisance tripping. Or not, depending on the installation environment. Best regards Gregg Regards, Peter L. Tarver, PE Product Safety Manager Sanmina-SCI Homologation Services San Jose, CA peter.tar...@sanmina-sci.com This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
Re: Unity Power Factor
Hi John: In the USA, this has largely been fixed by a change in the USA National Electrical Code. There must be quite a number of installations that are not yet upgraded. Where a problem existed, it was fixed by pulling another neutral. Are there any other problems appearing in the field which can be reliably determined as due to concentrations of non-linear loads of less than 3 kVA or so? Probably not. The only other problem that I know of is distribution transformer overheating. But, I believe such transformers are very much larger than 3 kVA, so 3 kVA of non-linear loads would have very little effect. Best regards, Rich This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
RTTE directive.
Anybody have a link to peruse and purchase this, and a brief synopsis. I assume it calls out the standard EMC tests - EN55022, EN55024, and Safety standards, along with a standard or section which deals with the intentional radiator portion of box, and harmonized frequencies etc. The device itself is a Wi-fi type box. Ethernet in, and RF out. Is that correct? Gary This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
RE: MRA US-EU: Sectoral Annex Safety suspended
Subject: RE: MRA US-EU: Sectoral Annex Safety suspended Dear Group, Having read the document given, can anybody explain what it means? You simple take the original terms and conditions and press the Delete key For the benefit of those that did not archive the original documents I will post a few Abstracts. Fortunately the CE Marking Directives were written BEFORE the MRA and therefore one simply reverts to what we were required to do before that date. The only comment that I would make is that some (if not all) Eu countries may increase their surveillance activities. This sounds like a queue for a presentation I shall be giving at the Austin (Tx) Product Safety Group entitled Preparing for the Economic Recovery - the SMART Use of Safety Files It will cover CONTENT How to write UL/CSA/CE Marking files, What MUST be in the LVD Technical File, Using report templates, working with subcontractors - working with prime contractors and OEM's Many CE Marking Technical Files are incomplete - so I will bring a sample of a completed CE Marking (LVD) Technical File and show how the UL Product Description can be used to avoid unnecessary duplication of effort. Prime contractors can spend an excessive amount of time monitoring sub-contractors - just as some sub-contractors could gain a competitive advantage by giving what their customer Needs. Many small companies will not embrace safety compliance processes as being too difficult - and loose opportunities. The presentation will be aimed at two interest groups: Large and Medium Sized companies with regulatory processes in place - this will help them harmonize documentation and to assess their sub-contract design and manufacture. Small companies that do not have formal compliance processes - this will help them demonstrate compliance to their (OEM) customers. I anyone wishes for further information of the presentation or the MRA we have set up a m...@test4safety.com account and forward information as it comes available. Best regards Gregg Gregg Kervill DipIM, MIMgt, MIEEE VP Engineering Test4Safety.com Inc PO Box 310, Reedville, VA 22539. USA Phone ( 804) 453-3141 Fax(804) 453-9039 http://www.test4safety.com/ Extracting from the MRA we have Article 2 PURPOSE OF THE AGREEMENT This Agreement specifies the conditions by which each Party will accept or recognize results of conformity assessment procedures, produced by the other Party's conformity assessment bodies or authorities, in assessing conformity to the importing Party's requirements, as specified on a sector-specific basis in the Sectoral Annexes, and to provide for other related cooperative activities. The objective of such mutual recognition is to provide effective market access throughout the territories of the Parties with regard to conformity assessment for all products covered under this Agreement. If any obstacles to such access arise, consultations will promptly be held. In the absence of a satisfactory outcome of such consultations, the Party alleging its market access has been denied, may, within 90 days of such consultation, invoke its right to terminate the Agreement in accordance with Article 21. Article 3 GENERAL OBLIGATIONS 1. The United States shall, as specified in the Sectoral Annexes, accept or recognize results of specified procedures, used in assessing conformity to specified legislative, regulatory, and administrative provisions of the United States, produced by the other Party's conformity assessment bodies and/or authorities. 2. The European Community and its Member States shall, as specified in the Sectoral Annexes, accept or recognize results of specified procedures, used in assessing conformity to specified legislative, regulatory and administrative provisions of the European Community and its Member States, produced by the other Party's conformity assessment bodies and/or authorities. 3. Where sectoral transition arrangements have been specified in Sectoral Annexes, the above obligations will apply following the successful completion of those sectoral transition arrangements, with the understanding that the conformity assessment procedures utilized assure conformity to the satisfaction of the receiving Party, with applicable legislative, regulatory and administrative provisions of that Party, equivalent to the assurance offered by the receiving Party's own procedures. There are then a series of EMC and Safety Annexes that specify the National Instruments (e.g. the LVD for EU ) The more useful article is (perhaps) this: Press Guidance -- Mutual Recognition Agreements Draft 6/13 * We are pleased today to announce the completion of a balanced package of Mutual Recognition Agreements (MRAs) between the United States and the European Union recognizing product test, inspection or certification results required by both governments in six economic sectors and eliminating the need for duplicative testing or approval on both
RE: question on test labs for multiple burst multiple stroke lightning
Hi Susan, I would check with Met Labs who bought the old TUV Santa Clara facility. Sorry, I don't have contact information for them. Best regards, Garry Hojan Strategic Compliance Services (SCS) www.regulatory-compliance.com Now that DO-160D, change 3 is published, does anyone have suggestions for test labs that can perform mulitple burst multiple stroke lightning? This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
RE: Circuit Breaker Tripping Dring Fault Tests
Thank you Richard – this situation vividly illustrates the danger of nuisances tripping – what message does that give to the Home Owner – “FIT A BIGGER FUSE!” That is why (some) CSA standards require a Turn-On Test – ON-OFF 10 times within a minute – protection devices MUST NOT OPERATE. I have been recommending this test to clients as GOOD ENGINEERING PRACTICE for the last 10 years. Best regards Gregg From: owner-emc-p...@majordomo.ieee.org [mailto:owner-emc-p...@majordomo.ieee.org]On Behalf Of richard.pitten...@hobartcorp.com Sent: Wednesday, January 29, 2003 7:58 AM To: Rich Nute Cc: emc-p...@majordomo.ieee.org Subject: Re: Circuit Breaker Tripping Dring Fault Tests Rich and group, Just one interesting point continuing the thought of fuse sizes for branch circuit protection. Awhile back, I was conducting a series of UL tests on a household food mixer. For one of the abnormal tests, UL required me to use a 30 A time-delay branch circuit fuse (lamp base) in the power supply to the unit under test. I thought this was extreme, believing that a 20 A fuse would be the maximum anyone would ever use. When questioned, I was told that such fuses are available and still in use, primarily in old residential areas. I visited my local hardware store and, sure enough, they were readily available, right along with the other more common sizes. You may want to consider this when considering such tests in the future. Good day, Richard Pittenger Agency Approval Engineer Hobart Corporation Rich Nute ri...@sdd.hp.com Sent by: owner-emc-p...@majordomo.ieee.org 01/28/2003 07:23 PM Please respond to Rich Nute To:pmerguerian2...@yahoo.com cc:emc-p...@majordomo.ieee.org Subject:Re: Circuit Breaker Tripping Dring Fault Tests Hi Peter: For safety, it is not clear from the standards whether the main branch circuit breaker tripping during fault conditions is an acceptable result. I see no reason why this should not be acceptable. What is your view? Some third party labs find it acceptable and others do not. Some products are provided with internal overcurrent protection and some are not. Clearly, those that do not have internal overcurrent protection rely on the branch circuit protection. If a product has an internal overcurrent protective device, and the fault is on the load side of that device, then the internal device should provide the protection and not the branch circuit device. (Otherwise, the internal device provides no protection, and might as well be removed.) If the fault is on the supply side of the internal device, then clearly the internal device cannot provide protection, and the branch circuit must provide the protection. The real question is whether or not the product is safe when the fault current is just below the operating point of the branch circuit device. Examining this question requires an understanding of the fault and whether its resistance can be high enough to not trip the branch circuit yet not create a hazardous condition (such as a fire). If the fault resistance always is no more than 120/20 = 6 ohms, then I would say that the branch circuit could be relied upon to provide protection against the fault. Note that in the USA, a 120-volt branch circuit can be provided with either a 15-amp or a 20-amp overcurrent device. Therefore, the product must be safe when the fault current is 20 amps, just below the overcurrent device operating point. That means that the product must be capable of dissipating 2400 watts without catching fire or destroying internal insulation that serves a safety purpose. Best regards, Rich This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list
RE: Circuit Breaker Tripping Dring Fault Tests
Peter - I agree that this is an acceptable result in the US and Canada. There are, however, additional considerations: For Pluggable Equipment Type A (to borrow a term from the 60950 standards), the largest branch circuit protection is assumed during testing (20A) and there is no further requirement. For Pluggable Equipment Type B and permanently connected equipment, it would then be necessary to specify the largest branch circuit protection device the equipment may be safely supplied from in the installation instructions. This would necessarily be the size of the protection involved during your testing. I am very interested in the nonNorth American view on this issue. Regards, Peter L. Tarver, PE Product Safety Manager Sanmina-SCI Homologation Services San Jose, CA peter.tar...@sanmina-sci.com From: peter merguerian Sent: Tuesday, January 28, 2003 11:54 AM Dear All, For safety, it is not clear from the standards whether the main branch circuit breaker tripping during fault conditions is an acceptable result. I see no reason why this should not be acceptable. What is your view? Some third party labs find it acceptable and others do not. Anyone can lead me to some inernational decisions regarding this issue? Thanks, Peter This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
RE: Circuit Breaker Tripping Dring Fault Tests
I am going to jump into this frey, here is my 2 cents... In the case of Medical Electronics, if the fault condition would cause more exposure of radiation to the patient than what was dialed in (X-Ray, MRI, Ultrasound) that would be a BAD thing. End of subject. dave garnier From: Lou Aiken [mailto:ai...@gulftel.com] Sent: Tuesday, January 28, 2003 11:00 PM To: peter merguerian; emc-p...@majordomo.ieee.org Subject: Re: Circuit Breaker Tripping Dring Fault Tests Here is what I think the requirements are: If the product remains safe, within the meaning of the standard, and the branch circuit overcurrent protection device does, or does not, operate as a result of fault testing, internal overcurrent is unnecessary. If the product does NOT remain safe, within the meaning of the standard, as a result of fault testing, internal overcurrent protection IS necessary, branch circuit overcurrent protection is inadequate, and internal overcurrent protection is necessary. Safe within the meaning of the standard: Does not exceed allowable fault temperature limits, does not catch fire, enclosure does not deform to the extent that parts involving the risk of electric shock or personal injury become exposed to the test finger or probe, will pass the required electric strength test after the fault, etc. IN order to be confident that the design is safe one must continue the fault testing until steady state conditions exist, OR for the maximum clearing time (for the resulting fault current) as stated in the standard for the particular overcurrent device. It is incorrect consider the result acceptable when the overcurrent device opens the circuit. The overcurrent device should be removed from the circuit and the current monitored during the fault test. Only approved fuses and circuit breakers should be specified if they are necessary make the product remain safe - within the meaning of the standard. There is a significant difference in the endurance and clearing limits between the UL and IEC standards for fuses and circuit breakers with the same current rating. Lou Aiken, LaMer LLC 27109 Palmetto Drive Orange Beach, AL 36561 USA tel ++ 1 251 981 6786 fax ++ 1 251 981 3054 Cell ++ 1 251 979 4648 - Original Message - From: peter merguerian mailto:pmerguerian2...@yahoo.com To: emc-p...@majordomo.ieee.org Sent: Tuesday, January 28, 2003 1:54 PM Subject: Circuit Breaker Tripping Dring Fault Tests Dear All, For safety, it is not clear from the standards whether the main branch circuit breaker tripping during fault conditions is an acceptable result. I see no reason why this should not be acceptable. What is your view? Some third party labs find it acceptable and others do not. Anyone can lead me to some inernational decisions regarding this issue? Thanks, Peter _ Do you Yahoo!? Yahoo! http://rd.yahoo.com/mail/mailsig/*http://mailplus.yahoo.com Mail Plus - Powerful. Affordable. Sign up ttp://rd.yahoo.com/mail/mailsig/*http://mailplus.yahoo.com now
Is pulse dialing still needed in Australia?
Hello All: I am trying to cost reduce an older, worldwide PSTN line interface design. This circuit contains a pulse dialing transient limiter that was needed to meet the pulse dialing requirements in the Netherlands and Australia. I would like to take this circuit out and restrict dialing to DTMF only in the Netherlands and Australia. I know that in the Netherlands, 100% of the PSTN lines now accept DTMF dialing, but I don't know if the same is true for Australia. A few years ago I was told that Australia would be 100% DTMF compatible soon, but I do not have reliable confirmation that this transition has been completed. Can any of you confirm that Australia's PSTN is now 100% DTMF compatible? Is there an official source that I can reference for this information? Also, can you confirm that there is no additional charge to use DTMF in Australia? I know this may sound ridiculous to those of you outside the USA, but when DTMF dialing was first introduced in the USA, the operating companies typically charged extra for the service. In some states, those charges are still being applied. Thanks, Joe Randolph Telecom Design Consultant Randolph Telecom, Inc. 781-721-2848 j...@randolph-telecom.com http://www.randolph-telecom.com This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
RE: Circuit Breaker Tripping Dring Fault Tests
Two points: To assure the safety of your product consider not whether it is safe if the breaker trips, but what is the failure mode of your product if the breaker (which you do not provide) does not trip. If you rely on the breaker, you need to properly specify it. In the US, there have been code changes to introduce a new device called an arc fault interrupting breaker which uses RF noise from an arc to trip a breaker at currents below normal overcurrent trip levels. This was introduced because there were many instances where an arc in power cords or similar places would generate enough energy to melt copper and blast it away. The molten copper is capable of starting fires. Often the breaker failed to trip during this momentary fault, and permitted arc tracking to cause repeated cycles of arcs. The message is, some types of failures are not well protected by ordinary overcurrent devices. This may or may not be relevant in your case. Bob Johnson ITE Safety This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
RE: 'DOW' of standards
Hi Group, Does anyone have a clear idea or knows a link that shows the differences between the old and new 61010 standard. Thank You Charlie Martin GE Panametrics From: iun...@servomex.com [mailto:iun...@servomex.com] Sent: Tuesday, January 28, 2003 9:33 AM To: emc-p...@majordomo.ieee.org Subject: 'DOW' of standards Dear Group, The OJ for the LVD (page C317/73) gives 1.1.2004 as being the date beyond which IEC 61010-1:1990/A2:1995 can no longer be used to presume conformance with the requirements of this Directive. After this date, can equipment previously assessed to this standard still be marketed without reassessment to the new standard (IEC 61010-1:2001)? If so, until when? Between 1.4.2001 (the 'dow' of IEC 61010-1:1990+A1:1992 (Modified)) and 1.1.2004 (the dow of IEC 61010-1:1990/A2:1995), can either IEC 61010-1:1990/A2:1995 or IEC 61010-1:2001 be used to presume conformance with the requirements of LVD? Apologies if the answers to the above have been covered before and are thus locked up in the group's archives. Ian Unwin Servomex Group Limited This email has been scanned for all viruses by the MessageLabs SkyScan service. This electronic message contains information from Servomex which may be privileged or confidential. The information is intended to be for the use of the individual(s) or entity named above. If you are not the intended recipient be aware that any disclosure, copying, distribution or use of the contents of this information is prohibited. If you have received this electronic message in error, please notify us immediately. Activity and use of the Servomex E-mail system is monitored to secure its effective operation and for other lawful business purposes. Communications using this system may also be monitored and may be recorded to secure effective operation and for other lawful business purposes. This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
RE: Circuit Breaker Tripping Dring Fault Tests
Jim I your case the required BASIC INSULATION is not present or adequate. BASIC INSULATION provides a level of protection. The branch circuit provides an additional level of protection if there is a failure of the BASIC INSULATION. The standard in this instance allows the designer to provide an alternate protection method to replace the BASIC INSULATION, with the requirement that it fails safe and it does not impact any other insulation system. Regards, Kurt Mikolajewski From: Jim Eichner [mailto:jim.eich...@xantrex.com] Sent: Tuesday, January 28, 2003 5:13 PM To: emc-p...@majordomo.ieee.org Subject: RE: Circuit Breaker Tripping Dring Fault Tests I've been trying to solve this one myself. I work with one pair of standards (UL458 / CSA107.1) where they specifically say that opening the branch circuit protection is acceptable during component fault testing, but NOT during short circuit tests done for the purposes of validating inadequate trace spacings (an easement offered in the standards in some situations). I've always been puzzled why we can't rely on branch circuit protection for both situations, but neither agency has been able to explain the difference to me. Jim Eichner, P.Eng. Regulatory Compliance Manager Xantrex Technology Inc. phone: (604) 422-2546 fax: (604) 420-1591 e-mail: jim.eich...@xantrex.com web: www.xantrex.com Confidentiality Notice: This email message, including any attachments, is for the sole use of the intended recipient(s) and may contain confidential and privileged information. Any unauthorized review, use, disclosure or distribution is prohibited. If you are not the intended recipient, please contact the sender by reply e-mail and destroy all copies of the original message. _ Do you Yahoo!? Yahoo! http://rd.yahoo.com/mail/mailsig/*http://mailplus.yahoo.com Mail Plus - Powerful. Affordable. Sign up ttp://rd.yahoo.com/mail/mailsig/*http://mailplus.yahoo.com now
RE: Circuit Breaker Tripping Dring Fault Tests
Peter, I do not have specifics, so I can only offer general information. The use of external breakers is acceptable for testing and certifying products that are hardwired to the electrical distribution of a facility for when fault current or withstand testing is required. In the US, the UL standards typically denote the overall requirements of the test and pass/fail criteria. The NEC may also detail specific information about over-current protection for specific devices. When an external breaker is utilized, it is required to be denoted in the installation instructions (UL requirement). However, this does present some issues when installed as the product may be preceded with a breaker that is different than what was tested. Remember, not all breakers are created equal. Therefore, testing of fault currents with one breaker may yield one result and testing of another manufacturer's breaker may have a second result. When products are cord connected, one is usually required to have internal over-current protection. However, I believe that this is a general guideline not a stead fast rule. Thanks, Bryan Cole Director of Engineering Product Safety Officer Emerson Network Power - Control Concepts Binghamton, New York 13902 Phone: 607.724.1352 extension 238 Fax: 607.724.0153 E-mail: bryan.c...@control-concepts.com www.Liebert.com www.Control-Concepts.com www.Edcosurge.com From: peter merguerian [mailto:pmerguerian2...@yahoo.com] Sent: Tuesday, January 28, 2003 2:54 PM To: emc-p...@majordomo.ieee.org Subject: Circuit Breaker Tripping Dring Fault Tests Dear All, For safety, it is not clear from the standards whether the main branch circuit breaker tripping during fault conditions is an acceptable result. I see no reason why this should not be acceptable. What is your view? Some third party labs find it acceptable and others do not. Anyone can lead me to some inernational decisions regarding this issue? Thanks, Peter _ Do you Yahoo!? Yahoo! Mail http://rd.yahoo.com/mail/mailsig/*http://mailplus.yahoo.com Plus - Powerful. Affordable. Sign up ttp://rd.yahoo.com/mail/mailsig/*http://mailplus.yahoo.com now The information in this electronic message may be privileged and confidential and is intended for the use of the individual(s) named above. If you are not the intended recipient, you are on notice that any unauthorized disclosure, copying, distribution, or taking of any action in reliance on the contents of these electronically transmitted materials is prohibited.
RE: MRA US-EU: Sectoral Annex Safety suspended
Ian, In short. There is an MRA between US and Europe that covers the Sectoral Annex EMC and Telecom. E.g for EMC, Conformity Assessment Bodies (CAB's) were assigned in the Europe for FCC regulation as wel as CAB's were assigned in US for EMC directive in Europe. An easy way for European Companies to get products approved locally in Europe for US and vice versa. And it works. The Sectoral Annex Safety could have given the same benefits to mftr's, but will be suspended now from EU side for the reasons as explained in the OJEC. So no need to panic, life could have been easier, but you can sleep peacefully. Regards, Kris From: iun...@servomex.com [mailto:iun...@servomex.com] Sent: woensdag 29 januari 2003 9:37 To: emc-p...@majordomo.ieee.org Subject: RE: MRA US-EU: Sectoral Annex Safety suspended Dear Group, Having read the document given, can anybody explain what it means? As an instrument manufacturer selling products into both the US and EU do I need to panic over this, or can I ignore it and sleep peacefully in my bed at nights? Regards Ian D Unwin Servomex Group Limited This email has been scanned for all viruses by the MessageLabs SkyScan service. This electronic message contains information from Servomex which may be privileged or confidential. The information is intended to be for the use of the individual(s) or entity named above. If you are not the intended recipient be aware that any disclosure, copying, distribution or use of the contents of this information is prohibited. If you have received this electronic message in error, please notify us immediately. Activity and use of the Servomex E-mail system is monitored to secure its effective operation and for other lawful business purposes. Communications using this system may also be monitored and may be recorded to secure effective operation and for other lawful business purposes. This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
Re: Circuit Breaker Tripping Dring Fault Tests
Rich and group, Just one interesting point continuing the thought of fuse sizes for branch circuit protection. Awhile back, I was conducting a series of UL tests on a household food mixer. For one of the abnormal tests, UL required me to use a 30 A time-delay branch circuit fuse (lamp base) in the power supply to the unit under test. I thought this was extreme, believing that a 20 A fuse would be the maximum anyone would ever use. When questioned, I was told that such fuses are available and still in use, primarily in old residential areas. I visited my local hardware store and, sure enough, they were readily available, right along with the other more common sizes. You may want to consider this when considering such tests in the future. Good day, Richard Pittenger Agency Approval Engineer Hobart Corporation Rich Nute ri...@sdd.hp.com Sent by: owner-emc-p...@majordomo.ieee.org 01/28/2003 07:23 PM Please respond to Rich Nute To:pmerguerian2...@yahoo.com cc:emc-p...@majordomo.ieee.org Subject:Re: Circuit Breaker Tripping Dring Fault Tests Hi Peter: For safety, it is not clear from the standards whether the main branch circuit breaker tripping during fault conditions is an acceptable result. I see no reason why this should not be acceptable. What is your view? Some third party labs find it acceptable and others do not. Some products are provided with internal overcurrent protection and some are not. Clearly, those that do not have internal overcurrent protection rely on the branch circuit protection. If a product has an internal overcurrent protective device, and the fault is on the load side of that device, then the internal device should provide the protection and not the branch circuit device. (Otherwise, the internal device provides no protection, and might as well be removed.) If the fault is on the supply side of the internal device, then clearly the internal device cannot provide protection, and the branch circuit must provide the protection. The real question is whether or not the product is safe when the fault current is just below the operating point of the branch circuit device. Examining this question requires an understanding of the fault and whether its resistance can be high enough to not trip the branch circuit yet not create a hazardous condition (such as a fire). If the fault resistance always is no more than 120/20 = 6 ohms, then I would say that the branch circuit could be relied upon to provide protection against the fault. Note that in the USA, a 120-volt branch circuit can be provided with either a 15-amp or a 20-amp overcurrent device. Therefore, the product must be safe when the fault current is 20 amps, just below the overcurrent device operating point. That means that the product must be capable of dissipating 2400 watts without catching fire or destroying internal insulation that serves a safety purpose. Best regards, Rich This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list
Re: Unity Power Factor
I read in !emc-pstc that Rich Nute ri...@sdd.hp.com wrote (in 200301281747.jaa29...@epgc264.sdd.hp.com) about 'Unity Power Factor' on Tue, 28 Jan 2003: Hi John: No, this is not much of an issue for the U.S. (unless your facility is actually affecting the utility); ... or frying the neutral conductors with third-harmonic current. In the USA, this has largely been fixed by a change in the USA National Electrical Code. There must be quite a number of installations that are not yet upgraded. When the load is largely electronic (off-line rectifiers) the Code now requires a larger neutral conductor in three- phase distributions. Yes, we do that in UK as well, for new installations. In some cases, the neutral, which is the same size as the phase conductors, is supplemented by another conductor, because the neutral current can, in an extreme case, exceed the phase current. Many constructions, while supplied from a three-phase source, are wired as single-phase. So, in this case, the neutral only carries the current of one phase, and we don't fry the neutral. That is a good solution. Are there any other problems appearing in the field which can be reliably determined as due to concentrations of non-linear loads of less than 3 kVA or so? -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk Interested in professional sound reinforcement and distribution? Then go to http://www.isce.org.uk PLEASE do NOT copy news posts to me by E-MAIL! This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
RE: EN55022:1998 + A1:2000
All I can see that my manager would prefer to use Neven's approach - it is probably much cheaper than buying clamps. However, does anybody have any practical experience of this? A reply from an accredited test house would be welcomed! Thanks Ian Gordon From: neve...@attbi.com [mailto:neve...@attbi.com] Sent: 29 January 2003 05:22 To: emc-p...@majordomo.ieee.org Subject: Re: EN55022:1998 + A1:2000 Instead of paying big bucks for the clamps (I am not sure what the price is, but I'm sure it is too much anyway :), why not buying a bucket of ferrite doughnuts that can be used over cables. Or, when possible, building in-line adapters out of sections of cables (maybe 1m long) and lining them up with ferrites. I'd select a combination of ferrites to cover 30 MHz to about 300 MHz. The high frequencies will be radiated anyway by the segment of the cables close to the DUT. Taking a little more thorough approach, I'd check the impedance with the lineup fixed over a defined height above a GND plane. (Not sure if that would make a big practical difference.) Neven A1 to EN55022:1998 requires the use of ferrite clamps on all cables leaving the table-top EUT for a connection outside the test site. Are there any other manufacturers of these clamps other than Fischer Custom Communications? Richard Woods Sensormatic Electronics Tyco International _ This e-mail has been scanned for viruses by the WorldCom Internet Managed Scanning Service - powered by MessageLabs. For further information visit http://www.worldcom.com This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
RE: MRA US-EU: Sectoral Annex Safety suspended
Dear Group, Having read the document given, can anybody explain what it means? As an instrument manufacturer selling products into both the US and EU do I need to panic over this, or can I ignore it and sleep peacefully in my bed at nights? Regards Ian D Unwin Servomex Group Limited This email has been scanned for all viruses by the MessageLabs SkyScan service. This electronic message contains information from Servomex which may be privileged or confidential. The information is intended to be for the use of the individual(s) or entity named above. If you are not the intended recipient be aware that any disclosure, copying, distribution or use of the contents of this information is prohibited. If you have received this electronic message in error, please notify us immediately. Activity and use of the Servomex E-mail system is monitored to secure its effective operation and for other lawful business purposes. Communications using this system may also be monitored and may be recorded to secure effective operation and for other lawful business purposes. This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
Re: EN55022:1998 + A1:2000
Instead of paying big bucks for the clamps (I am not sure what the price is, but I'm sure it is too much anyway :), why not buying a bucket of ferrite doughnuts that can be used over cables. Or, when possible, building in-line adapters out of sections of cables (maybe 1m long) and lining them up with ferrites. I'd select a combination of ferrites to cover 30 MHz to about 300 MHz. The high frequencies will be radiated anyway by the segment of the cables close to the DUT. Taking a little more thorough approach, I'd check the impedance with the lineup fixed over a defined height above a GND plane. (Not sure if that would make a big practical difference.) Neven A1 to EN55022:1998 requires the use of ferrite clamps on all cables leaving the table-top EUT for a connection outside the test site. Are there any other manufacturers of these clamps other than Fischer Custom Communications? Richard Woods Sensormatic Electronics Tyco International --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
Re: Circuit Breaker Tripping Dring Fault Tests
Here is what I think the requirements are: If the product remains safe, within the meaning of the standard, and the branch circuit overcurrent protection device does, or does not, operate as a result of fault testing, internal overcurrent is unnecessary. If the product does NOT remain safe, within the meaning of the standard, as a result of fault testing, internal overcurrent protection IS necessary, branch circuit overcurrent protection is inadequate, and internal overcurrent protection is necessary. Safe within the meaning of the standard: Does not exceed allowable fault temperature limits, does not catch fire, enclosure does not deform to the extent that parts involving the risk of electric shock or personal injury become exposed to the test finger or probe, will pass the required electric strength test after the fault, etc. IN order to be confident that the design is safe one must continue the fault testing until steady state conditions exist, OR for the maximum clearing time (for the resulting fault current) as stated in the standard for the particular overcurrent device. It is incorrect consider the result acceptable when the overcurrent device opens the circuit. The overcurrent device should be removed from the circuit and the current monitored during the fault test. Only approved fuses and circuit breakers should be specified if they are necessary make the product remain safe - within the meaning of the standard. There is a significant difference in the endurance and clearing limits between the UL and IEC standards for fuses and circuit breakers with the same current rating. Lou Aiken, LaMer LLC 27109 Palmetto Drive Orange Beach, AL 36561 USA tel ++ 1 251 981 6786 fax ++ 1 251 981 3054 Cell ++ 1 251 979 4648 - Original Message - From: peter merguerian mailto:pmerguerian2...@yahoo.com To: emc-p...@majordomo.ieee.org Sent: Tuesday, January 28, 2003 1:54 PM Subject: Circuit Breaker Tripping Dring Fault Tests Dear All, For safety, it is not clear from the standards whether the main branch circuit breaker tripping during fault conditions is an acceptable result. I see no reason why this should not be acceptable. What is your view? Some third party labs find it acceptable and others do not. Anyone can lead me to some inernational decisions regarding this issue? Thanks, Peter _ Do you Yahoo!? Yahoo! Mail http://rd.yahoo.com/mail/mailsig/*http://mailplus.yahoo.com Plus - Powerful. Affordable. Sign up ttp://rd.yahoo.com/mail/mailsig/*http://mailplus.yahoo.com now
RE: Automotive v. EMC Directives
Automotive products must comply with the Automotive Directive - this actually requires additional elements beyond the EMC Directive. Safety issues are as one would expect - Fire and Energy Hazard - and are potentially more serious than mains operated equipment because you do not usually have 12 gallons of gas sitting on you stereo. About 30 years ago I watched as a guy fitted a temporary Parking Light to the cigarette outlet of his car - opened the window - fitted the light (bracket) over the windowpane - closed the window then locked and closed the car door. We all watched is astonishment as the wiring began to smolder and the car filled with smoke. I did not wait to find out what happened next Now that's what you call a non-compliance!! Best regards gregg From: owner-emc-p...@majordomo.ieee.org [mailto:owner-emc-p...@majordomo.ieee.org]On Behalf Of Hudson, Alan Sent: Tuesday, January 28, 2003 12:34 PM To: EMC-pstc (E-mail) Subject: Automotive v. EMC Directives G'Day! Is anyone familiar with the standards needed to comply with the Automotive *and* the EMC Directives? How do they compare? Or to put it another way, if an item of equipment was known to be compliant with the Automotive Directive, is it likely that it would therefore meet the requirements of the EMC Directive? Alan -- Alenia Marconi Systems Scotland This email and any attachments are confidential to the intended recipient and may also be privileged. If you are not the intended recipient please delete it from your system and notify the sender. You should not copy it or use it for any purpose nor disclose or distribute its contents to any other person. This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
