Re: Calibration of test equipment
As I understand it the interpretation to have tracibility to your national authority through equipment used only for calibration originated with NAMAS. Some other accreditors have picked it up since then. The requirement need not be that onerous. You can calibrate your own equipment traceably to your national authority using equipment that you send out for calibration. Where the instrument is cheap (multimeter) we buy an extra and use it only for calibration. Where it is expensive (oscope, receiver), we use it for calibration only directly after it returns from outside calibration (or inside tracible cal) and after we have calibrated our secondary equipment with it we put it into regular service for the year. If you manage your yearly calibration cycle well this shouldn't crimp your style too much. The key is not to have equipment in your calibration chain back to the national authority that has been used for non-calibration purposes between the time of its calibration and that of the secondary calibration. The idea is to have high confidence that the tracibilty chain is intact. If a piece of equipment in the chain has been used daily in regular rough and tumble testing it is seen as having a much higher probability of operating outside of its tolerances. In my experience the outside cal houses are pretty tough on their gear too, so I am not sure that much is gained. I personally think this interpretation is overly severe, but we comply with it because we want our test reports to be accepted by authorities who think this process is reasonable. To directly answer your specific question about a signal generator used in immunity: If it is being used as an uncalibrated signal source in the measurement and you are using a power meter or receiver for tracibility then you can use that signal generator, even if it went off a cliff the day before. If you are relying on the calibrated output level that the signal generator says it is putting out, then you should not have used that instrument in non-calibration use since its last calibration. Jon. "Flinders, Randall" wrote: > Does this mean that a signal generator that is used for Radiated > Immunity testing should not be used to calibrate Pre-Amps and Cables? > How about Antenna Calibration? Can you use the same receiver you use on > the OATS to calibrate those? I know this is a common practice with > Commercial Test Labs. > > Is there guidance as to what types of equipment can be used for both lab > use and for the calibration of other equipment? > > michael.sundst...@nokia.com wrote: > > > > I think there is a special requirement to keep the calibration equipment > > separate from the EMC equipment. In other words the calibration equipment > > can only be used for the calibration process and not for testing EMC. > > > > > Michael Sundstrom > > > Product Test Technician EMC > > > Nokia Mobile Phones, Dallas PCC > > > > > > * Email michael.sundst...@nokia.com > > > % Desk (972) 374-1462 > > > *Mobile (817) 917-5021 > > > * Fax (972) 374-0901 > > amateur call: KB5UKT > > > > --- > > 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: > > Michael Garretson:pstc_ad...@garretson.org > > Dave Healddavehe...@mediaone.net > > > > 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://www.rcic.com/ click on "Virtual Conference Hall," > > --- > 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: > Michael Garretson:pstc_ad...@garretson.org > Dave Healddavehe...@mediaone.net > > For policy questions, send mail to: > Richard Nute: ri...@ieee.org > Jim Bacher: j.bac...@ieee.org > > All emc-pstc postings are archived and search
Re: FCC Part 15 Class B
See 15.101. Class B personal computers and peripherals may use either the Certification or Declaration of Conformity equipment authorization procedure. "Other class B digital devices and peripherals" are subject to the Verification equipment authorization procedure. Be careful as Verification is not the same as Declaration of Conformity with different labeling requirements, test site accreditation requirements, etc. See 47 CFR Part 2 for detailed descriptions of the equipment authorization procedures. Jon Curtis. Courtland Thomas wrote: > Hello Group, > > I would like to know if it is permissible to self verify to Class B for ITE. > I know it can be done for Class A, but I am not sure about Class B. The > interesting thing is that I posed the question to a contact at the FCC and > the answer I got was "No idea". > > Courtland Thomas > Patton Electronics > > --- > This message is from the IEEE EMC Society Product Safety > Technical Committee emc-pstc discussion list. > > 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: > Jim Bacher: jim_bac...@mail.monarch.com > Michael Garretson:pstc_ad...@garretson.org > > For policy questions, send mail to: > Richard Nute: ri...@ieee.org -- Jon D. Curtis, P.E. Director of Engineering Curtis-Straus LLC One Stop Laboratory for NEBS, EMC, Product Safety, and Telecom Testing. 527 Great Road Littleton, MA 01460 USA Voice 978-486-8880 Fax 978-486-8828 email: jcur...@curtis-straus.com WWW.CURTIS-STRAUS.COM --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. 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: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
Re: SAR Measurements
measured > > regarding > > SAR if the radiated power is less than 1 mW (0 dBm)? > > Or is this only the experience that these kind of devices never exeed the > > limits of table 2? > > > > Any hint welcome > > > > Thanks > > > > Best Regards > > > > Lothar Schmidt > > Technical Manager EMC/Bluetooth, > > BQB, Competent Body > > Cetecom Inc. > > 411 Dixon Landing Road > > Milpitas, CA 95035 > > Phone: +1 (408) 586 6214 > > Fax: +1 (408) 586 6299 > > > > > > > > > > --- > > This message is from the IEEE EMC Society Product Safety > > Technical Committee emc-pstc discussion list. > > > > 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: > > Jim Bacher: jim_bac...@mail.monarch.com > > Michael Garretson:pstc_ad...@garretson.org > > > > For policy questions, send mail to: > > Richard Nute: ri...@ieee.org > > > > > > --- > This message is from the IEEE EMC Society Product Safety > Technical Committee emc-pstc discussion list. > > 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: > Jim Bacher: jim_bac...@mail.monarch.com > Michael Garretson:pstc_ad...@garretson.org > > For policy questions, send mail to: > Richard Nute: ri...@ieee.org -- Jon D. Curtis, P.E. Director of Engineering Curtis-Straus LLC One Stop Laboratory for NEBS, EMC, Product Safety, and Telecom Testing. 527 Great Road Littleton, MA 01460 USA Voice 978-486-8880 Fax 978-486-8828 email: jcur...@curtis-straus.com WWW.CURTIS-STRAUS.COM --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. 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: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
Re: Downloadable CE marks
We have it in bit map in the guest center at www.curtis-straus.com -Jon. Mike Stone wrote: > Good Morning-Is anyone aware of a web site that has downloadable CE > marks?Thanks in advance. Regards, Michael Stone > L.S. Compliance > W66 N220 Commerce Court > Cedarburg, Wi 53012 > V 262-375-4400 > F 262-375-4248 -- Jon D. Curtis, P.E. Director of Engineering Curtis-Straus LLC One Stop Laboratory for NEBS, EMC, Product Safety, and Telecom Testing. 527 Great Road Littleton, MA 01460 USA Voice 978-486-8880 Fax 978-486-8828 email: jcur...@curtis-straus.com WWW.CURTIS-STRAUS.COM
Re: FCC certifications
Whoa! Part 68 requires trade names to be disclosed to the commission in a mod filing. I agree with your statement for Part 15. For Part 68 you can either have the new company file for a re-certification which requires a letter of permission from the original registrant or the original registrant can add the new company's name to their registration as a trade name by doing a modification filing. In a re-certification the new company gets a new FCC Registration Number. If they are added as a trade name, then the registration number stays the same. wo...@sensormatic.com wrote: > You may label any FCC Certified product with any brand name and no change is > required to the certifications. The FCC ID numbers of the product identify > the holder of the grants and those numbers are not related to the brand name > appearing on the product. > > Richard Woods > > -- > From: k...@i-data.com [SMTP:k...@i-data.com] > Sent: Friday, September 29, 2000 9:00 AM > To: emc-p...@majordomo.ieee.org; t...@world.std.com > Subject: FCC certifications > > Hi all, > > I can't find the answer to the following questions in the > information I > have from FCC I hope that sombody can help me. > > We have both FCC part 15 certified products and FCC part 68 > certified > products. Now a OEM costumer wants to have our product with his name > on FCC > certified. Both a product with part 15 only and one also including > part > 68. > > Are we allowed to use our FCC ID on his labels or do we need to > apply for a > new FCC ID ? > > (The OEM version is our product in a new color and without our name) > > If we need a new FCC ID what is the procedure for this ? Hopefuly we > can > transfere the approvals directly. > > Best regards, > > Kim Boll Jensen > i-data > Denmark > > --- > This message is from the IEEE EMC Society Product Safety > Technical Committee emc-pstc discussion list. > > 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: > Jim Bacher: jim_bac...@mail.monarch.com > Michael Garretson:pstc_ad...@garretson.org > > For policy questions, send mail to: > Richard Nute: ri...@ieee.org > -- Jon D. Curtis, P.E. Director of Engineering Curtis-Straus LLC One Stop Laboratory for NEBS, EMC, Product Safety, and Telecom Testing. 527 Great Road Littleton, MA 01460 USA Voice 978-486-8880 Fax 978-486-8828 email: jcur...@curtis-straus.com WWW.CURTIS-STRAUS.COM --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. 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: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
Re: VCCI application
There is a pdf version of the form in the guest center on our web site at www.curtis-straus.com -Jon Curtis. Jim Bacher wrote: > forwarding for : bgilmar...@cereva.com > > Reply Separator > Subject:VCCI application > Author: "Gilmartin; Bob" > Date: 9/27/00 1:46 PM > > Hello group, > Does anybody have an application for VCCI they can forward to me. I > went to the VCCI website and it's a Catch-22-I can't download an application > for membership until I have a membership (i.e. username and password). > There is also no link to email VCCI. > > Bob Gilmartin > Sr. Regulatory Engineer > Cereva Networks, Inc. > 3 Network Drive > Marlboro, MA 01752-3083 > (508) 486-9660 x3412 phone > (508) 486-9776 fax > > --- > This message is from the IEEE EMC Society Product Safety > Technical Committee emc-pstc discussion list. > > 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: > Jim Bacher: jim_bac...@mail.monarch.com > Michael Garretson: pstc_ad...@garretson.org > > For policy questions, send mail to: > Richard Nute: ri...@ieee.org -- Jon D. Curtis, P.E. Director of Engineering Curtis-Straus LLC One Stop Laboratory for NEBS, EMC, Product Safety, and Telecom Testing. 527 Great Road Littleton, MA 01460 USA Voice 978-486-8880 Fax 978-486-8828 email: jcur...@curtis-straus.com WWW.CURTIS-STRAUS.COM --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. 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: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
Re: NEBS: GR-63 Altitude Test Profile
Hi, At the last two NEBS conferences Mike Bentley of USWest stated that all he was concerned about was the EUT performance at high temperature. What changes at altitude is the heat capacity of air. Thus it becomes more difficult to cool equipment because the air is "thin". USWest is the RBOC which is most concerned with this test as they are the only one to my knowledge with COs above 12,000 feet. We run the altitude test at 50C for frames and 55C for shelves. We allow the EUT to stabilize within the chamber and we also determine the temperature at which equipment starts to fail in the event that the EUT has a problem at the extreme temperature. AT&T NEDS does have a non-operational test at 40,000 feet which we run at ambient temperature and humidity as an unpressurized airplane bay is unlikely to be very hot.. BTW, the next NEBS conference is in Baltimore next week. See www.800teachme.com for details. -Jon Curtis David Spencer wrote: > Hi Jeffrey, > Our friends at Telcordia do seem to enjoy listing requirements where we > would least expect them. GR63 is no exception. For altitude, the limits > called out in R4-8 [74] and O4-10[76] for Table 4-4 are the general > temperature/humidity limits for long and short term exposure. The > application of those criteria can be found in Table 4.5 in the 182 hour > profile. > > It is my belief that you test to at 4000m using the profile from table 4.5, > unless you wanted to make a profile of your own that covered the same ground > over a longer period of time, using Table 4-4 for the limits, rates of > change, and duration. If the EUT cannot tolerate the resulting temperature > rise from the 4000m altitude, it will be necessary to retest at 1800 to meet > R4-8. The failure is documented in the NEBS data submitted to the carrier > who decides if it is something he wants you to do something about before he > purchases you equipment. I do not think it is necessary to test 1800m if > you have passed the table 4-5 profile at 4000m. > > Don't forget: Objective requirements are not elective. The tests must be > performed and the results documented. It is by this means that decisions > are made about making the objective a mandatory requirement down the road. > > Good Luck! > Dave Spencer Compliance Engineer > Oresis Communications, Inc. > 14670 NW Greenbrier Parkway, Beaverton, OR 97006 > * dspen...@oresis.com * http://www.oresis.com > * (503) 466-6289 * (503) 533-8233 > > -Original Message- > From: Collins, Jeffrey [mailto:jcoll...@ciena.com] > Sent: Monday, September 25, 2000 6:36 AM > To: 'emc-p...@ieee.org ' > Subject: NEBS: GR-63 Altitude Test Profile > > Group, > > GR-63 sections 4.1.3 & 5.1 do not give a definitive testing profile for > Altitude testing. If you have completed this test what profile did you use? > Is there a customer specification from an RBOC or CLEC that you found to be > definitive. It appears that by only addressing these sections you could have > to retest down the road for a customer located in a high altitude > environment. Which Telco has the most stringent internal specifications for > this test? > > Points to be considered are: > > * Max Altitude > 4000m > > * Temperature at max Altitude > Profile in Table 4-5 > > * Relative Humidity > Profile in Table 4-5 > > * Length of time at Max Altitude > 182 hrs > > Thanks in advance, > > Jeffrey Collins > MTS, Principal Compliance Engineer > Ciena Core Switching Division > jcoll...@ciena.com > www.ciena.com > > --- > This message is from the IEEE EMC Society Product Safety > Technical Committee emc-pstc discussion list. > > 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: > Jim Bacher: jim_bac...@mail.monarch.com > Michael Garretson:pstc_ad...@garretson.org > > For policy questions, send mail to: > Richard Nute: ri...@ieee.org > > --- > This message is from the IEEE EMC Society Product Safety > Technical Committee emc-pstc discussion list. > > 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: > Jim Bacher: jim_bac...@mail.monarch.com > Michael Garretson:pstc_ad...@garretson.org > > For policy questions, send mail to: > Richard Nute: ri...@ieee.org -- Jon D. Curtis, P.E. Director of Engineering Curtis-Straus LLC One Stop
TCBs are designated
Telecom Certification Bodies have been designated by the FCC. Anyone who wants a copy of the public notice can email me as it does not seem to have appeared on the FCC web site yet. -- Jon D. Curtis, P.E. Certification Manager Curtis-Straus LLC Telecom Certification Body 527 Great Road Littleton, MA 01460 USA Voice 978-486-8880 Fax 978-486-8828 email: jcur...@curtis-straus.com WWW.CURTIS-STRAUS.COM
Employment opportunity
Are you searching for an exciting employment opportunity? Curtis-Straus, an Electronics Testing Laboratory in Littleton, MA is looking for EMC engineers to staff our test and design laboratory. Curtis-Straus LLC is the fastest growing testing laboratory in New England! We offer an entrepreneurial environment with unlimited growth opportunities. Curtis-Straus specializes in Electromagnetic Compatibility and Electromagnetic Interference (EMC/EMI) testing, NEBS testing, Product Safety testing and Telecommunications testing. Our ideal candidate will possess the following skills and qualities: Strong Technical Skills Talent for Solving Technical Challenges Strong Written and Verbal Communications Skills Must Enjoy Daily Client and Team Member Interaction Desire to Learn If you are looking for an opportunity to establish yourself as a future leader in a growing company, this may be your opportunity. Please forward or email your resume to: j...@curtis-straus.com Curtis-Straus LLC Attn: Dept. H 527 Great Road Littleton, MA 01460 -- Jon D. Curtis, P.E. Director of Engineering Curtis-Straus LLC One Stop Laboratory for EMC, Product Safety, and Telecom Testing. 527 Great Road Littleton, MA 01460 USA Voice 978-486-8880 Fax 978-486-8828 email: jcur...@curtis-straus.com WWW.CURTIS-STRAUS.COM --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. 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: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
Re: List of upcoming dates for standards
We have posted the last OJ notice which lists the dates of effect on our web site at www.conformity.com. "Martin Rowe (TMW)" wrote: > Does anyone know of a web site that lists when the various EMC > standards will go into effect? If not, would such a web age be > useful? > > /\ > | Martin Rowe | / \ > | Senior Technical Editor | /\ /\ > | Test & Measurement World | / \/ \/\ > | voice 617-558-4426 |/\ /\ / \/ > | fax 617-928-4426 | \/ \/ > | e-mail m.r...@ieee.org | \ / > | http://www.tmworld.com |\/ > > > --- > This message is from the IEEE EMC Society Product Safety > Technical Committee emc-pstc discussion list. > > 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: > Jim Bacher: jim_bac...@mail.monarch.com > Michael Garretson:pstc_ad...@garretson.org > > For policy questions, send mail to: > Richard Nute: ri...@ieee.org -- Jon D. Curtis, P.E. Director of Engineering Curtis-Straus LLC One Stop Laboratory for EMC, Product Safety, and Telecom Testing. 527 Great Road Littleton, MA 01460 USA Voice 978-486-8880 Fax 978-486-8828 email: jcur...@curtis-straus.com WWW.CURTIS-STRAUS.COM --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. 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: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
Re: European Standards in conflict with the EMC directive
I suspect that given the group's proclivity to talk endlessly on almost any topic that the real reason that you got no response was that no one understood your question sufficiently to answer it. You obviously have an alarm system. You have some other EN standard which is in conflict with the alarm EMC standard. You have some authorizing bodies which don't accept your data. You are unhappy about the situation. What standard is in conflict with the alarm standard? Why is it being applied to your product? Does your product fall into multiple product families? What approvals are you approaching a certifier for? Who is the certifier? BTW: attempting to change the way CENELEC does business is futile. You will be attempting a remedy on government time frames for a problem with commercial time frames. You are advocating from a small constituency (alarm systems) against what is likely a larger constituency. Your best bet is to figure out what they want, the easiest way to do it, and give it to them. Kevin Harris wrote: > Hello Again Group, > > Well the group's total silence on this point is indeed interesting. Does > nobody know how to proceed or is everyone just keeping their corporate heads > down : > Please reply offline if you feel uneasy answering this question in a public > forum. > > Regards > > Kevin Harris > > -Original Message- > From: Kevin Harris [mailto:harr...@dscltd.com] > Sent: Monday, November 08, 1999 10:38 AM > To: EMC-PSTC (E-mail) > Subject: European Standards in conflict with the EMC directive > > Greetings, > > Is there an established procedure for demanding the withdrawal of EMC > clauses within standards who's primary purpose is industry regulation, not > EMC. In my company's industry there is an established product family > standard for EMC (EN50130-4) but the good people at CENELEC seem to be > ignoring the EMC directive, and have published within the last year or two, > EN standards which include EMC testing clauses, with methods that are at > odds with the EMC document EN50130-4 published in the OJ. Especially > troubling to me is the fact that all of the test organisations that test for > the industry regulation specification do not accept either third party or > self declarations that the product is EMC compliant. I do not wish to test > the same product more than once for a single market. What path do you > recommend I follow to demand the repeal of these clauses. > > Best Regards, > > Kevin Harris > Manager, Approval Services > Digital Security Controls > 3301 Langstaff Road > Concord, Ontario > CANADA > L4K 4L2 > > Tel +1 905 760 3000 Ext. 2378 > Fax +1 905 760 3020 > > - > > - > This message is coming from the emc-pstc discussion list. > To cancel your subscription, send mail to majord...@ieee.org > with the single line: "unsubscribe emc-pstc" (without the > quotes). For help, send mail to ed.pr...@cubic.com, > jim_bac...@monarch.com, ri...@sdd.hp.com, or > roger.volgst...@compaq.com (the list administrators). -- Jon D. Curtis, PE Curtis-Straus LLC j...@curtis-straus.com Laboratory for EMC, Safety, NEBS, SEMI-S2 and Telecom 527 Great Roadvoice (978) 486-8880 Littleton, MA 01460 fax (978) 486-8828 http://www.curtis-straus.com - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: "unsubscribe emc-pstc" (without the quotes). For help, send mail to ed.pr...@cubic.com, jim_bac...@monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators).
Re: Horn antennas, pre-amplifier, and return loss measurement
My higher horns came from Millitech. Leslie Bai wrote: > EMCO has no horn over 40GHz. > > --- "WOODS, RICHARD" wrote: > > > > Try EMCO for horns and MITEQ for preamps. > > > > -- > > From: Leslie Bai [SMTP:leslie_...@yahoo.com] > > Sent: Thursday, August 12, 1999 1:15 PM > > To: 'emc-p...@majordomo.ieee.org' > > Subject: Horn antennas, pre-amplifier, and return > > loss measurement > > > > > > Hi, Folks, > > > > Is there anyone can direct me to some sources > > of horn antennas & preamplifiers. > > > > What I need are sets of horn antenna for spurious > > emissions testing to meet FCC Part 101. > > > > 1 to 18GHz, > > 18 to 26.5GHz, 26.5 to 40GHz, or 18 to 40GHz > > instead, > > 40 to 60GHz, 50 to 75GHz, or 40 to 75GHz instead, > > 75 to 110GHz, 110 to 170GHz, or 75 to 170GHz > > instead. > > > > Due to the significant space loss over 110GHz, I > > guess > > I also need a set of preamplifier from 110 to > > 170GHz. > > > > I am also studying on return loss measurement > > methodologies to meet ETSI requirement for > > radios RF port. Since NAMAS calibration of > > network analyzer may cost thousands bucks, > > I am wondering if I could achieve a good result > > (in terms of accuracy and uncertainty) using > > spectrum analyser and waveguide coupler. > > If anyone by any chance has an ready error model > > of the test setup using spectrum analyzer and > > waveguide coupler, I appreciate you could share > > with me to short my research path. > > > > Thanks in advance. > > > > Leslie Bai > > Senior Compliance Engineer > > Compliance Quality Manager > > Digital Microwave Corporation > > 170 Rose Orchard Way > > San Jose, CA 95134 > > Tel: (408)-944-1754 > > > > > > _ > > Do You Yahoo!? > > Get your free @yahoo.com address at > > http://mail.yahoo.com > > > > > > - > > This message is coming from the emc-pstc discussion > > list. > > To cancel your subscription, send mail to > > majord...@ieee.org > > with the single line: "unsubscribe emc-pstc" > > (without the > > quotes). For help, send mail to > > ed.pr...@cubic.com, > > jim_bac...@monarch.com, ri...@sdd.hp.com, or > > roger.volgst...@compaq.com (the list > > administrators). > > > > > > - > > This message is coming from the emc-pstc discussion > > list. > > To cancel your subscription, send mail to > > majord...@ieee.org > > with the single line: "unsubscribe emc-pstc" > > (without the > > quotes). For help, send mail to ed.pr...@cubic.com, > > jim_bac...@monarch.com, ri...@sdd.hp.com, or > > roger.volgst...@compaq.com (the list > > administrators). > > > > > > > > _ > Do You Yahoo!? > Bid and sell for free at http://auctions.yahoo.com > > - > This message is coming from the emc-pstc discussion list. > To cancel your subscription, send mail to majord...@ieee.org > with the single line: "unsubscribe emc-pstc" (without the > quotes). For help, send mail to ed.pr...@cubic.com, > jim_bac...@monarch.com, ri...@sdd.hp.com, or > roger.volgst...@compaq.com (the list administrators). -- Jon D. Curtis, PE Curtis-Straus LLC j...@curtis-straus.com Laboratory for EMC, Safety, NEBS, SEMI-S2 and Telecom 527 Great Roadvoice (978) 486-8880 Littleton, MA 01460 fax (978) 486-8828 http://www.curtis-straus.com - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: "unsubscribe emc-pstc" (without the quotes). For help, send mail to ed.pr...@cubic.com, jim_bac...@monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators).
Re: Spam Mail
Hi Michael, (Disclosure: My company publishes Conformity Newsmagazine, a possible competitor with ITEM.) Something similar happened to one of my employees when they subscribed to ITEM. We didn't know what to do with all the stuff we got. I looked into it and found that there was a "trick" involved. On the ITEM subscription card it says "FREE SUBSCRIPTION QUALIFICATION - Answer ALL questions in this section", below this is a list of stuff like "Antennas" with check boxes. Just above the check boxes it says "FOR ADDITIONAL INFORMATION...". So, you check boxes about your interest to get a free subscription AND you also get tons of info from all the people that make the stuff for the boxes you checked. It could have been a confusing mistake in the way the form was put together, but I doubt it. In ITEMs defense, advertisers place way too much credence on how many leads they get back today. Most people who respond to an ad are wired in and either call the company direct or hit their web site rather than using the old, slow lead generation system. Companies that advertise need to qualify incoming leads by asking them where they came from when they come in by web or phone or fax or email. That's the only way they are going to figure out what advertising is working today. Most magazines are having to educate their advertisers to expect lower traditional lead generation and it must have been very tempting to juice the lead generation up. Michael Taylor wrote: > Greetings All. > I have recently been inundated with catalogues & phone calls from vendors. > After some sleuthing I discovered I had been slimed > by one of the magazines we (all) receive. It appears they are attempting to > increase there customer response index by sending > advertisers false sales leads. In my case, vendors reported that I had > responded via a "Reader Response Card" to recent ad's, which I had not. > I am concerned enough about this practice to send this note. I believe that > it represents the lowest form of deception and must be stopped. > > The magazine is free and performs a valuable service in keeping the EMC > community informed. Vendors are nice enough to support > this magazine through advertising. This symbiotic relationship benefits > everyone as long as everyone plays by the rules. When I need information > about I a product I expect to receive a prompt reply. With false leads > vendors are needlessly burdened and replies take too long. Additionally, > I got a "note" from the manager of our mail room about the extraordinary > volume of mail I was receiving. The large number of voice mails > from vendors overloaded the voice mail system. (I heard about that also). > If any other members of the group have received the same treatment I urge > you to contact the vendors and tell them you were slimed > and inform the magazine you want it stopped. > > I'll step down from my soap box now and go lock myself in the chamber. > > Best Regards, > Michael Taylor > Principal EMC Engineer > HACH Company > > - > This message is coming from the emc-pstc discussion list. > To cancel your subscription, send mail to majord...@ieee.org > with the single line: "unsubscribe emc-pstc" (without the > quotes). For help, send mail to ed.pr...@cubic.com, > jim_bac...@monarch.com, ri...@sdd.hp.com, or > roger.volgst...@compaq.com (the list administrators). -- Jon D. Curtis, PE Curtis-Straus LLC j...@curtis-straus.com Laboratory for EMC, Safety, NEBS, SEMI-S2 and Telecom 527 Great Roadvoice (978) 486-8880 Littleton, MA 01460 fax (978) 486-8828 http://www.curtis-straus.com - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: "unsubscribe emc-pstc" (without the quotes). For help, send mail to ed.pr...@cubic.com, jim_bac...@monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators).
Follow Up Services/Factory Inspections
I am writing an article on preparing for factory inspections. Please share with me your "gotchas" and any advice that a person should know before the inspector arrives. What did the inspector look for? What documents did you need to provide? Any references on what to expect published by the NRTLs or others such as NEMA? Thanks in advance for your comments. -- Jon D. Curtis, PE Curtis-Straus LLC j...@curtis-straus.com Laboratory for EMC, Safety, NEBS, SEMI-S2 and Telecom 527 Great Roadvoice (978) 486-8880 Littleton, MA 01460 fax (978) 486-8828 http://www.curtis-straus.com - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: "unsubscribe emc-pstc" (without the quotes). For help, send mail to ed.pr...@cubic.com, jim_bac...@monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators).
Re: EN 61000=4 again
Check the scopes. EN 300 386-2 is for the Central Office side of the demarkation point. It is for equipment which IS the network. That leaves EN55024 for equipment that is on the customer premise side of the demarkation point or is ITE that doesn't connect to the network. EN55024 is for telco terminal equipment. If your equipment goes in both places, test the extra non-overlap parts of the two standards and declare conformity to both. As for the generics, product family standards superceed the generics. For ITE that go in heavy industrial environments it may be appropriate to increase the levels of specific tests of EN55024 to the levels of EN50082-2 in order to prevent customer disatisfaction with your product, but you can CE mark your ITE for any environment with EN55024 alone. After all conflicting standards are withdrawn for EN55024 in 2001, it would be inappropriate to CE mark an ITE product based on test data to EN50082-2 alone. EN55024 has specific test configurations and among other things, extra surge tests to cover the special product family needs of ITE. Cal Whiteley wrote: > Thanks to all of you for your info - but I'm still a bit confused Is > the applicable standard for telecommunications terminal equipment EN > 55024 or is it EN 300 386-2 ? It's my understanding that both standards > cite EN 61000-4 sections but that there is a difference- EN 61000-4-8 is > called out in EN 55024 but not in > EN 300 386-2. Which is the applicable standard? > > - > This message is coming from the emc-pstc discussion list. > To cancel your subscription, send mail to majord...@ieee.org > with the single line: "unsubscribe emc-pstc" (without the > quotes). For help, send mail to ed.pr...@cubic.com, > jim_bac...@monarch.com, ri...@sdd.hp.com, or > roger.volgst...@compaq.com (the list administrators). -- Jon D. Curtis, PE Curtis-Straus LLC j...@curtis-straus.com Laboratory for EMC, Safety, NEBS, SEMI-S2 and Telecom 527 Great Roadvoice (978) 486-8880 Littleton, MA 01460 fax (978) 486-8828 http://www.curtis-straus.com - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: "unsubscribe emc-pstc" (without the quotes). For help, send mail to ed.pr...@cubic.com, jim_bac...@monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators).
Re: EMC Books
Hi Ron, I've posted reveiws of a number of EMC books at www.conformity.com/book_store.html Disclosure: I also sell the books there. ron_pick...@hypercom.com wrote: > To all, > > I am interested in knowing (and maybe others are, too) about the really good > EMC books that are out and about. They may be practical, theoretical or > anywhere in between. Areas of interest are, but are not limited to PWBs, > backplanes and systems with considerations for design, troubleshooting, and > noise reduction. > > For those having such handy references up on their shelves or just knowing of > any, please feel free to reply. Replies may be either posted on this forum or > sent to me privately. Either way, I will post the summary of results once the > responses die off. > > BTW, I already know about a few books and will include those in the summary. > > This list of EMC references will likely be a valuable asset to any EMC > professional, particularly those new to the game. Who knows, maybe we all > might > benefit from such a list. > > OK, let me have it/them. > > Best regards, > Ron Pickard > ron_pick...@hypercom.com > > - > This message is coming from the emc-pstc discussion list. > To cancel your subscription, send mail to majord...@ieee.org > with the single line: "unsubscribe emc-pstc" (without the > quotes). For help, send mail to ed.pr...@cubic.com, > jim_bac...@monarch.com, ri...@sdd.hp.com, or > roger.volgst...@compaq.com (the list administrators). -- Jon D. Curtis, PE Curtis-Straus LLC j...@curtis-straus.com Laboratory for EMC, Safety, NEBS, SEMI-S2 and Telecom 527 Great Roadvoice (978) 486-8880 Littleton, MA 01460 fax (978) 486-8828 http://www.curtis-straus.com - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: "unsubscribe emc-pstc" (without the quotes). For help, send mail to ed.pr...@cubic.com, jim_bac...@monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators).
Re: 1000Base-T (IEEE 802.3ab) vs. EMI on UTP (Unshielded Twisted Pairs)
According to an artical by Lee Goldberg in Electronic Design November 16, 1998, Giga bit ethernet uses"PAM-5" modulation scheme with a partial-response spectrum shaping of the form 0.75 + 0.25z(-1) to limit emissions to within the FCC limits. This simple filter shapes the spectrum so that its power spectral density falls below that of existing 100Bast T ethernet. Since 100BaseT is compliant, it is likely that Gigabit will be compliant. The magic is in the spreading algorithim which spreads the energy uniformly over a very broad range while maintaining the bipolar average. As far as I know, all ethernet standards incorporate these modulation schemes in order to comply when transmitted over unshielded cables. Since emissions are measured with a 120kHz bandwidth (from 30-1000MHz), you can pump out a lot of power if you spread it over a large frequency (say 100MHz). If the other end is intellegent enough to decode your scrambled bits, and you code for emissions reduction/spreading the result is communications at a high rate with emissions in compliance with the FCC limits. Donald Kimball wrote: > The IEEE 802.3ab defines the new Gigabit Ethernet Standard (i.e. > 1000Base-T). This Local Area Network (LAN) can use 4 twisted pairs of > unshielded copper cable (Category-5) at 100m maximum operating at 250Mb/s > per pair in full-duplex bi-directional mode. This standard is designed to > utilize existing LAN cables such as older 10Base-T and 100Base-T networks. > The signaling (i.e. baud) rate is 125MHz per pair using 5-level Pulse > Amplitude Modulation (PAM) . This probably results in the fundmental energy > at 62.5MHz given that the signal must be bipolar to be compatible with > transformers. Vendors such as Broadcom Corp. have developed single chip > copper cable interfaces for this new standard. > > In the past, standards using unshielded cables, such as 100Base-T, > 10Base-T, T1, E1, etc, have had signaling rates less than 30MHz, so that > the fundamental frequency was below the 30MHz FCC and CISPR starting > frequency for radiated emissions. However, 1000Base-T has a 125MHz > signaling rate. A common mode current of less than 10uA at 30MHz at 1/2 of > wavelength can yield an emission level equal to or greater than the Class B > level. In addition, the 4 twisted pairs are all phase locked to each other. > The intentional differential mode current is about 10mA, so the trans > hybrid balance needs to be better than 60dB. This is achievable with the > hybrid at the component level, but not at the system level with 100m of Cat > 5 cable attached. > > Conclusion, I think that 1000Base-T (IEEE 802.3ab) on unshielded Category > 5 cable is doomed to fail EMI. Anybody ever try a test? Any other opinions? > > Don Kimball > > - > This message is coming from the emc-pstc discussion list. > To cancel your subscription, send mail to majord...@ieee.org > with the single line: "unsubscribe emc-pstc" (without the > quotes). For help, send mail to ed.pr...@cubic.com, > j...@gwmail.monarch.com, ri...@sdd.hp.com, or > roger.volgst...@compaq.com (the list administrators). -- Jon D. Curtis, PE Curtis-Straus LLC j...@curtis-straus.com Laboratory for EMC, Safety, NEBS, SEMI-S2 and Telecom 527 Great Roadvoice (978) 486-8880 Littleton, MA 01460 fax (978) 486-8828 http://www.curtis-straus.com - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: "unsubscribe emc-pstc" (without the quotes). For help, send mail to ed.pr...@cubic.com, j...@gwmail.monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators).
Re: CE+ CE = CE
boratory) the similar > concept > of "modular approval", i.e. if each separate module is > conformant the > whole assembly could be deemed to be, was decisively rejected. > > Hope this helps. > > -- > Bill Lyons - b...@lyons.demon.co.uk / w.ly...@ieee.org > > - > This message is coming from the emc-pstc discussion list. > To cancel your subscription, send mail to majord...@ieee.org > with the single line: "unsubscribe emc-pstc" (without the > quotes). For help, send mail to ed.pr...@cubic.com, > j...@gwmail.monarch.com, ri...@sdd.hp.com, or > roger.volgst...@compaq.com (the list administrators). > > - > This message is coming from the emc-pstc discussion list. > To cancel your subscription, send mail to majord...@ieee.org > with the single line: "unsubscribe emc-pstc" (without the > quotes). For help, send mail to ed.pr...@cubic.com, > j...@gwmail.monarch.com, ri...@sdd.hp.com, or > roger.volgst...@compaq.com (the list administrators). -- Jon D. Curtis, PE Curtis-Straus LLC j...@curtis-straus.com Laboratory for EMC, Safety, NEBS, SEMI-S2 and Telecom 527 Great Roadvoice (978) 486-8880 Littleton, MA 01460 fax (978) 486-8828 http://www.curtis-straus.com - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: "unsubscribe emc-pstc" (without the quotes). For help, send mail to ed.pr...@cubic.com, j...@gwmail.monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators).
Re: EMC limits.
Passing is passing. The limit is passing. Curtis-Straus will write you a report which says you pass if we observe zero dB or greater margin. Just don't expect to pass with great certainty on the next sample. I would strongly suggest that you consider requiring a margin if the product will evolve and need to be retested or if you sell to a systems integrator who may have his/her system tested. But it is up to you. 4 dB is a nice margin. Now for the interesting comments: Consider that some are lobbying for a new limit which is lower than the old limit by the uncertainty of measurement. There has always been an uncertainty. In fact, it's been going down as the techniques of EMI measurement become better understood. And emissions problems have been fairly benign from equipment tested to the limit with the older measuring techniques (those with high uncertanty). What this discussion needs is a quantification of the old uncertainty. For argument let's say it's 7dB. If we want to take uncertainty into account in a pass/fail decision, we should compare the emission to the limit plus 7dB minus the actual uncertainty. In other words, discussions of uncertainty should be viewed as a way to raise the limit while maintaining the protection objectives of various regulations. Or, uncertainty was never considered before, so consideration of it now without a limit increase is in fact a limit decrease. Since the existing limit has been working to control interference for some time now, any decrease is likely to be a brake on economic growth (it'll cost more to comply) with little benefit to the community (no reduction in non-existant emissions problems). Jon Curtis. Chris Dupres wrote: > EMC Folk. > > I have been reading all the learned submissions of what constitutes the > acceptable emission limits for EMC purposes. Most of you are very clever, > very technical, and I'm in awe of all of you. > > But there seems to be a bit of a missed point here. EMC in Europe relates > to the EMC Directive, which was born of the SIngle Market arrangements > between Euro States, and which were born of the Treaty of Rome way back > before my kids were born. > > The ultimate purpose of EMC Standards/limits is to provide a level trading > platform for Euro countries, so that all conditions are equal in the market > place, and that no-one can steal a lead over someone else by dropping > technical standards and therefore saving costs and putting cheaper goods on > the market. It follows that perhaps we should look at these limits in the > same way that the packaging industry looks at filling cans and bottles, or > the way car drivers treat speed limits. i.e, that the EMC emission limits > are a target in absolute terms, and if you can show honest intent in > achieving them, then the legislation has achieved it's aim. > > If I carry out an honest emissions test on a piece of equipment, and the > graph is below the line by the thickness of the pen, then I believe that > the spirit of the EMC Directive has been met. If this acceptance level was > an absolute amount, such as money in banking, then I would allow a % for > measurement error, but it isn't, it's an objective. No-ones head is going > to explode if the emissions are 0.5dB over limit, and in all honesty > dropping the emissions by 0.5dB can usually be achieved by moving a cable > or snapping on a ferrite sleeve. Hardly enough to change the whole balance > of trade in Europe is it? > > So, if I carry out properly conducted tests, with the equipment working > normally, and it shows emissions right on the limit, then I think the EMC > Directive has been followed, and the equipment can be CE marked with > honesty and placed on the market. > > Just a tuppence worth (what's THAT in Euro's?) > > Chris Dupres > Surrey, UK. > > - > This message is coming from the emc-pstc discussion list. > To cancel your subscription, send mail to majord...@ieee.org > with the single line: "unsubscribe emc-pstc" (without the > quotes). For help, send mail to ed.pr...@cubic.com, > j...@gwmail.monarch.com, ri...@sdd.hp.com, or > roger.volgst...@compaq.com (the list administrators). -- Jon D. Curtis, PE Curtis-Straus LLC j...@curtis-straus.com Laboratory for EMC, Safety, NEBS, SEMI-S2 and Telecom 527 Great Roadvoice (978) 486-8880 Littleton, MA 01460 fax (978) 486-8828 http://www.curtis-straus.com - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: "unsubscribe emc-pstc" (without the quotes). For help, send mail to ed.pr...@cubic.com, j...@gwmail.monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators).
Re: Room grounding
As I understand it, Lingren connects the shielded rooms they build back to the main building ground point by a separate ground wire. The conduit is disconnected by use of a plastic sleave. I assume they do this because the AC filters incorporated in the shielded room include LARGE capacitors to the shielded room walls. Effectively the leakage through these capacitors turns the ENTIRE room surface into an AC electrode with respect to building ground. This leakage current is potentially leathal unless returned back to the source where the neutrals of the building are tied to ground at the circuit panel. Not grounding the room (if it incorporates standard room filters) should not be considered acceptable. If there is an regular outlet on an adjacent building wall, then a lethal hazard will exist between a metal test instrument pluged into that outlet and the room surface. I would hazard a bet that most room installations are not well enough controlled to insure that building ground and a separate room ground are NEVER allowed to meet. Consider that no sparks will fly if it happens, but hearts may stop. People automatically consider dead metal as ground. I would also caution against those in this thread who rely on conduit. Conduit breaks, is removed, etc. For high leakage threats only a dedicated ground wire of suitable gage to carry the total fault current of the supply should be employed. This is not about a single fault problem. You have a hazardous condition with NO fault because of filter leakage if you do not ground the room to the building ground at the circuit panel. Watch out for LISNs Also. The design of all lisns incorporate LARGE capacitors to ground for filtering. Without a ground connection on the LISN case, high leakage threats exist. Most use LISNs bonded to the ground plane which addresses this threat as long as the ground plane is connected to the building ground. The debate on reduction of noise and effects on EMC results should continue, BUT personel safety comes FIRST and should not be compromised. lfresea...@aol.com wrote: > Mike, > > sorry you disagree. > > Inside the room, all equipment is referenced to the room itself, there is no > new safety risk introduced by the room being grounded differently. > > Outside the room, again, all equipment is referenced tightly to the room, so > the operator does not see any differential. > > Should lightning strike the building, then true, the building earth potential > may lift, but the operator is protected because he is referenced to the room > which will not move much because the energy has been dissipated by the > building earthing system. > > I state again this is for performance reasons, and is accepted practice. In a > true Faraday shielded room, earthing the room is not even neccessary. Mind > you, since these don't exist off the shelf, I'll stick to grounding using my > original guidlines. NEC inspectors, when the rationale is explained to them > have little problem. However, I have come across situations were the two > unique earths were tied by a very heavy inductor > > Best regards, > > Derek N. Walton > > - > This message is coming from the emc-pstc discussion list. > To cancel your subscription, send mail to majord...@ieee.org > with the single line: "unsubscribe emc-pstc" (without the > quotes). For help, send mail to ed.pr...@cubic.com, > j...@gwmail.monarch.com, ri...@sdd.hp.com, or > roger.volgst...@compaq.com (the list administrators). -- Jon D. Curtis, PE Curtis-Straus LLC j...@curtis-straus.com Laboratory for EMC, Safety, NEBS, SEMI-S2 and Telecom 527 Great Roadvoice (978) 486-8880 Littleton, MA 01460 fax (978) 486-8828 http://www.curtis-straus.com - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: "unsubscribe emc-pstc" (without the quotes). For help, send mail to ed.pr...@cubic.com, j...@gwmail.monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators).
Dell EMC contact
I am looking for a contact within the EMC department at Dell Computer. Please reply only to my personal email account. Thanks, Jon D. Curtis, PE Curtis-Straus LLC j...@curtis-straus.com Laboratory for EMC, Safety, NEBS, SEMI-S2 and Telecom 527 Great Roadvoice (978) 486-8880 Littleton, MA 01460 fax (978) 486-8828 http://www.curtis-straus.com - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.com with the single line: "unsubscribe emc-pstc" (without the quotes). For help, send mail to ed.pr...@cubic.com, ri...@sdd.hp.com, or roger.volgst...@compaq.co (the list administrators).
Re: isopropyl alcohol
What if anything are laboratories doing to "calibrate" chemical solutions? Seems to me that as an ISO Guide 25 laboratory, an analysis of the batch of the solution to nationally tracible standards by an ISO Guide 25 laboratory is required. What are other laboratories doing to calibrate chemical solutions? Jon D. Curtis, PE Curtis-Straus LLC j...@curtis-straus.com Laboratory for EMC, Safety, NEBS, SEMI-S2 and Telecom 527 Great Roadvoice (978) 486-8880 Littleton, MA 01460 fax (978) 486-8828 http://www.curtis-straus.com On Fri, 10 Jul 1998, Chris Dupres wrote: > Hi Ned. > > You wrote: > standards require isopropyl alcohol for durability of marking test. > e.g. IEC 1010-1, Clause 5.3 and IEC 601-1, Clause 6.1.z. > > The difference in opinion is in the concentration. The standards just > state "isopropyl alcohol". Some say 70% others say 100%. What are > other people using? > > > I use a material labelled 'Isopropyl Alcohol' for the rub test. That's > what it says on the tin, and I can only assume that it is 100%. I am sure > that it is 100% because spills evaporate very quickly and leave no water > behind, I'm sure that if it was diluted the water would remain long after > the IPA had gone. > > Does that make sense?. > > Chris Dupres > Surrey, UK. >
Re: Multiple EMC requirements for Fire Equipment in EU
For the standards route to compliance only standards listed in the OJ with reference to the EMC directive can be used. EN50130-4 is listed, EN54-2 is not. With regards to the EMC directive, EN50130-4 wins. You will still need to do what your customers want you to do and that may include EN54-2, but there is no need to do it under the EMC directive. I'd advise that you attempt to get them to accept EN50130-4 in leu of the immunity tests you describe. Jon D. Curtis, PE Curtis-Straus LLC j...@curtis-straus.com Laboratory for EMC, Safety, NEBS, SEMI-S2 and Telecom 527 Great Roadvoice (978) 486-8880 Littleton, MA 01460 fax (978) 486-8828 http://www.curtis-straus.com
Massachusetts jobs
HIRING EMC or Product Safety or SEMI S2 Engineers in Massachusetts Curtis-Straus, a progressive entrepreneurial test and design laboratory, is seeking engineers to join our team. Our requirements include strong technical skills, a talent for solving technical challenges, and strong communications skills. The ideal candidate will strive to assure client satisfaction and enjoy daily interaction with clients and team members. Send resume to Department T, Curtis-Straus, 527 Great Road, Littleton, MA 01460. Or use email to cs...@world.std.com. Web:http://www.curtis-straus.com/ Jon D. Curtis, PE Curtis-Straus LLC j...@curtis-straus.com Laboratory for EMC, Safety, NEBS, SEMI-S2 and Telecom 527 Great Roadvoice (978) 486-8880 Littleton, MA 01460 fax (978) 486-8828 http://www.curtis-straus.com
Recent EMC OJ standards list
The April 3, 1998 OJ notice listing all EMC standards and their dates of withdrawal has been posted on the Conformity web site. http://www.conformity.com Happy surfing. Jon D. Curtis, PE Curtis-Straus LLC j...@world.std.com Laboratory for EMC, Safety, NEBS, SEMI-S2 and Telecom 527 Great Roadvoice (978) 486-8880 Littleton, MA 01460 fax (978) 486-8828 http://world.std.com/~csweb
Job opportunities
HIRING Electrical Engineers in Massachusetts For EMC or Product Safety or SEMI S2 careers Curtis-Straus, a progressive entrepreneurial test and design laboratory, is seeking engineers to join our team. Our requirements include strong technical skills, a talent for solving technical challenges, and strong communications skills. The ideal candidate will strive to assure client satisfaction and enjoy daily interaction with clients and team members. Send resume to Department T, Curtis-Straus, 527 Great Road, Littleton, MA 01460. Or use email to cs...@world.std.com. Web:http://www.curtis-straus.com/ Jon D. Curtis, PE Curtis-Straus LLC j...@world.std.com Laboratory for EMC, Safety, NEBS, SEMI-S2 and Telecom 527 Great Roadvoice (978) 486-8880 Littleton, MA 01460 fax (978) 486-8828 http://www.curtis-straus.com/
Re: Canada CISPR 22 Conducted Emissions Answer
I think you overlooked a detail. The FCC allows you to use the LIMITS of CISPR 22, but requires the ANSI TEST METHODS with regards to cable manipulation, etc. Since the CISPR 22 techniques are relatively unspecified and are being modified in committee to match ANSI C63.4, a test report for all countries would use the CISPR 22:1993 limits and the ANSI test methods now. Jon D. Curtis, PE Curtis-Straus LLC j...@world.std.com Laboratory for EMC, Safety, NEBS, SEMI-S2 and Telecom 527 Great Roadvoice (978) 486-8880 Littleton, MA 01460 fax (978) 486-8828 http://world.std.com/~csweb On Thu, 19 Feb 1998 fryd...@norand.com wrote: > > Subject: Canada CISPR 22 Conducted Emissions Answer > Author: frydave at NOR2CCPO > Date:2/19/98 10:39 AM > > > Thank you for all responses. > > Clarification for testing and report requirements. Based on the fact the > European Union, FCC and Industry Canada have endorsed CISPR 22, a test > report > that covers Global requirements would be as follows. > > The following assumes the use of universal power supplies or supplies with > 120-230 volt settings available. > > -Radiated emissions to CISPR 22-1993 using CISPR peripheral and cable > maximization procedure. To satisfy the worst case requirements, > investigative testing must be done at 120 VAC 60 Hz and 230 VAC 50 Hz. > Perform final radiated emissions testing at the worst case operating > voltage. >Justify the operating voltage as the worst case configuration within the > text of the report. > > -Conducted emissions is also done to CISPR 22 range of 150 kHz to 30 MHz > and > testing must be performed at both 120 VAC 60 Hz and 240 VAC 50 Hz. Again > use > the peripheral and cable maximization procedure for CISPR 22-1993. Report > the > conducted emissions for both voltage settings within the test report. > > Once the European Commission has adopted CISPR 22-1997, all testing will > use > the peripheral and cable maximization procedure outlined within the 1997 > version, essentially the ANSI C63.4-1992 procedure. > > [hopefully Canada will also adopt the new CISPR 22-1997 requirements for > maximization of cables and peripherals] > > Dave Fry, Sr. EMC Specialist > Intermec Technologies Corporation > Norand Mobile Systems Division > EMC Test Laboratory > Internet: fryd...@norand.com >
Products outside LVD range
This one's more appropriate for the EMC-PSTC List :) -JDC. From: "D. E. Smith" Subject: Outside the LV Directive Range What do you do it your product has a working voltage outside the LVD range? While the LVD has a range of 50 to 1000 volts DC or 75 to 1500 volts AC a product like a high voltage test probe may not fall into this range because they measure voltages from 6 to 40 KV. What happens if someone would use one of these probes to test a circuit that falls within the LVD? Can we test to IEC 1010 Category III and if it passes can we claim compliance? RCIC - http://www.rcic.com Regulatory Compliance Information Center
Re: Lightning and Power Cross Testing
See remarks below. Jon D. Curtis, PE Curtis-Straus LLC j...@world.std.com One-Stop Laboratory for EMC, Product Safety and Telecom 527 Great Roadvoice (508) 486-8880 Littleton, MA 01460 fax (508) 486-8828 http://world.std.com/~csweb On Thu, 31 Jul 1997, Jerry Martin wrote: > I've been asked to test a network powered (-130 Vdc) product to > GR-1089-CORE for lightning and power cross. > > Does anyone out there have any suggestions on how to do this testing > while the product is powered? > > The problem is that if you apply 1000 V, 10/1000 uSec, 100 A to tip/ring > while the product is powered, you will damage the power source. I've > looked into using series inductance followed by an MOV and capacitor, but > I'm not sure if all the energy is getting to the UUT. Another problem is > that my tester applies a short to tip and ring prior to the application > of the test voltage. To protect the power supply add as much resistance as you can push the required amount of current through. Then add a 2-10mH inductor (you can buy commercial or cut up a line filter). Make the protection two pole with capacitors (5uF to ground ought to do) and non-linear with MOVs rated just over 130VDC. To keep the EUT running during the power supply shorting action use a large capactor in series with the generator. You'll need to use a fairly large one to avoid cliping the trailing edge of the short circuit current waveform. Without running calcs, I believe the ballpark is 1000uF for a 5-10% reduction in short circuit fall time. Hopefully, your generator is a little long so that you can shorten it down to 1000uS. > > The same problem doing power cross (600 Vac, 1 A, 1 Sec). Applying this > kind of voltage to the power source will damage it. Is there a way for > the UUT to remain line powered and provide protection to the power > source? Seems to me you could use something like the loop simulator from part 68. Protect the DC power source with 10 Henry inductors in series with each lead. Check this out by placing a capacitor (say 1000uF) across the power supply end of the inductors (sans power supply) and measure the voltage on the cap with a volt meter (it ought to be real low). Be cautious with this set up because inductors with less than 1500V dielectric withstand capabilities are likely to become "fire or fragmentation" hazards. With Surge and Overvoltage testing eye protection is not optional. > > Has anyone had similar problems? > > Thank you very much for any suggestions. > > Jerry >
Re: FCC Requirements
A class C does not exist in the Unintentional Radiator FCC Rules. However if you are a license-exempt low power transmitter, then the rules under SUBPART C of 47 CFR Part 15 apply to your product. If the specification is REAL OLD, they could also be applying the pre-1989 Subpart C rules for receivers which actually are grandfathered until 1999. Jon D. Curtis, PE Curtis-Straus LLC j...@world.std.com One-Stop Laboratory for EMC, Product Safety and Telecom 527 Great Roadvoice (508) 486-8880 Littleton, MA 01460 fax (508) 486-8828 http://world.std.com/~csweb On Thu, 12 Jun 1997, PHILLIP FORD wrote: > > > A customer has told us that he requires our product to meet > FCC Class C. > > Can anyone out there point me towards the right information please? > > (Or is it just a typo?) > > Regards, PFORD at HVTVM GBXYR7PW at IBMMAIL > Phillip Ford phil_f...@uk.xyratex.com > ext 3255 tel:+44 (0)1705 443255 fax:+44 (0)1705 499315 > Engineering Lab, 871/24-22X Y R A T E X >
Re: LVD and standards listed on the OJ
Dear Marty, I note that EN61131-2 was listed in the OJ under the EMC directive on December 6, 1995. By that light, you should comply with its requirements as long as you are subject to the EMC directive (ie you're not a subassembly without a direct use). Jon D. Curtis, PE Curtis-Straus LLC j...@world.std.com One-Stop Laboratory for EMC, Product Safety and Telecom 527 Great Roadvoice (508) 486-8880 Littleton, MA 01460 fax (508) 486-8828 http://world.std.com/~csweb On Wed, 11 Jun 1997, Martin Ginty wrote: > Sorry about the previous attempt!! I hit the send button by accident! > * > > Dear All, > > hopefully one of you out there can help me with this, > > My company has recently been contacted by an organisation stating that > our product (programmable logic controller) should comply with the > requirements of EN61131-2 (the standard for programmable logic > controllers) as it is listed on the OJ for the Low Voltage Directive. No > problem with that, we already comply with the safety aspects of this > standard. However, they also think that we should test to and satisfy > the functional requirements as well as the safety requirements. To my > knowledge LVD is concerned with the safety of circuits operating at > voltages above 50VAC or 75VDC. The directive states that the safety > requirements only need to be met and most of the standards listed on the > OJ for this directive are applicable to the safety requirements portions > only. Also at the beginning of EN61131-2 it states that this standard > takes precedence over all other standards EXCEPT basic safety standards. > EN61131-2 isn't actually a safety standard as such, it covers design and > definition of PLC systems as well as design requirements for circuits > operating within the voltage ranges that fall within the scope of the > directive (and a whole bunch of other stuff I don't want to go into!). > However, as many of the circuits within a PLC system are SELV they don't > fall within the scope of the directive. > > Is there any justification for this organisation to demand this? > Am I missing something here? > > Best regards > > Martin Ginty > Mitsubishi Nagoya Works > FA systems department >
RE: MDoC & References to Harmonized Standards
Dear Tony, For ITE you should have on your MDoC: EMC Directive:89/339/EEC as Amended by 93/68/EEC EN55022:1994 and EN55022 A1:1995 for RF emissions EN50082-1:1992 or EN50082-2:1995 for immunity Low Voltage Directive: 73/23/EEC as Amended by 93/68/EEC EN60950 for safety and you might have: EN60555-2, EN60555-3, or EN61000-3-2 and EN61000-3-3 and any other standards or directives applicable to your specific product. Jon D. Curtis, PE Curtis-Straus LLC j...@world.std.com One-Stop Laboratory for EMC, Product Safety and Telecom 527 Great Roadvoice (508) 486-8880 Littleton, MA 01460 fax (508) 486-8828 http://world.std.com/~csweb On Wed, 4 Jun 1997, Tony Fredriksson wrote: > > Hi, > > Thumbing through "Compliance Engineering" Magazine, the > 1996 Reference Guide, I note on page A8 that EN 55022:1994 was > published in the OJ on September 16, 1995. > > That would mean that the Generic Emissions Standard, > EN 50081-1:1992, should not be referenced on an MDoC > for ITE, whereas EN 55022:1994 should be. This assumes > that EN 55014, EN 60555-2, and EN 60555-3, the other > standards referenced by EN 50081-1:1992 are not > applicable to the ITE product in question. > > Am I interpreting this correctly? > > Thx, > tony_fredriks...@netpower.com >
Re: EN50091-2 - EMC Requirements for UPS
EN 50091-2:1995 was published in the OJ on February 29, 1996. It has a dow of March 1, 1996. Jon D. Curtis, PE Curtis-Straus LLC j...@world.std.com One-Stop Laboratory for EMC, Product Safety and Telecom 527 Great Roadvoice (508) 486-8880 Littleton, MA 01460 fax (508) 486-8828 http://world.std.com/~csweb On Fri, 16 May 1997 jeich...@statpower.com wrote: > > Does anyone out there know if this EN has been published in the OJ yet? The > standard is dated October 15, 1996, but I don't know its OJ status, dow, > etc. > > Any help the forum can offer will be greatly appreciated. > > Thanks, > > Jim Eichner > Statpower Technologies Corporation > jeich...@statpower.com > Any opinions expressed are those of my invisible friend >
Spread Spectrum Transmitter Approvals
Dear EMC-PSTCer's, I have a client who wants to obtain transmitter approvals in the following countries for the following transmitter types. If you have information or offer a service/testing please send me email. Thank you. The questions are: Is 433.92MHz narrowband allowed for short range transmitters? Is 2.44 GHz narrowband allowed for short range transmitters? Is 2.44 GHz spread spectrum allowed? What is the spread spectrum frequency range? Countries: Norway Japan South Korea Phillipines Israel Saudi Arabia South Africa Brazil Chile Austrailia Once again please reply to me and thanks. Jon D. Curtis, PE Curtis-Straus LLC j...@world.std.com One-Stop Laboratory for EMC, Product Safety and Telecom 527 Great Roadvoice (508) 486-8880 Littleton, MA 01460 fax (508) 486-8828 http://world.std.com/~csweb
Read any good (EMC) books lately?
I am conducting a search for good technical works. I am interested in articles, books and other publications which you might consider useful or otherwise state-of-the-art. I would particularly like to find works which support their thesis with experimental data. Please send recommendations directly to me. I will then post a compendium back to the group once the information is in. I am especially interested in the following subjects: Use of spread spectrum clocks for EMI reduction Measurement errors introduced by wooden frame EMI sites High speed multi-layer PCB layout strategies to minimize EMI Comparison of modern day logic families (ground bounce?) Software control of transient behavior introduced by EMC Hardening of thermocouple, RTDs, and other small signal circuits to withstand radio frequency interference. Thanks in advance for your cooperation. Best Regards, Jon D. Curtis, PE Curtis-Straus LLC j...@world.std.com One-Stop Laboratory for EMC, Product Safety and Telecom 527 Great Roadvoice (508) 486-8880 Littleton, MA 01460 fax (508) 486-8828 http://world.std.com/~csweb
Re: Latest EN Standards
Whoa! Think you missed one. EN55104 is titled Immunity requirements for household appliances, tools and similiar apparatus. It's was published in the OJ on September 16, 1995 with a date of withdrawal of January 1, 1996 for conflicting standards. You can't use the generic (EN50082-1) anymore. Jon D. Curtis, PE Curtis-Straus LLC j...@world.std.com One-Stop Laboratory for EMC, Product Safety and Telecom 527 Great Roadvoice (508) 486-8880 Littleton, MA 01460 fax (508) 486-8828 http://world.std.com/~csweb On 2 Apr 1997 barron_ma...@tandem.com wrote: > ma > The following standards apply to the noted product types: > > ITEM EMISSIONSIMMUNITY > > #1EN55013 EN55020 > #2EN55014 EN50082-1 > > >Sincerely, > >Manny Barron >Tandem Computers > > om>, lp...@mail.arc.nasa.gov, ltran@SENT 04-02-97 FROM SMTPGATE > (rldxa...@hk.super.net) > > Can anyone advise me the latest EMC EN standards for the following > categories in order to comply with Council Directive 89/336/EEC. > > 1. Sound & television broadcast receivers and associated equipment, i.e., > radios, televisions, audio/video combination units. > > 2. Household electrical appliances, i.e., hairdryers, fans, fan heaters. > > Thanks and regards, > > Raymond Li > Dixons Stores Group >
re: Austrailian Immunity implementation date for ITE (fwd)
I asked the sma about immunity testing in Austrailia as part of the EMC framework and received the following reply. Jon D. Curtis, PE Curtis-Straus LLC j...@world.std.com One-Stop Laboratory for EMC, Product Safety and Telecom 527 Great Roadvoice (508) 486-8880 Littleton, MA 01460 fax (508) 486-8828 http://world.std.com/~csweb -- Forwarded message -- List-Post: emc-pstc@listserv.ieee.org Date: 1 APR 97 08:57:01 EST From: dbrum...@sma.gov.au To: j...@world.std.com Subject: re: Immunity implementation date for ITE Dear Jon Immunity is not required at this stage. We intend to require it in future for selected products that are particularly susceptible, but we have no implementation date as yet. David Brumfield Radiocommunications Standards Team dbrum...@sma.gov.au
Re: ICES-003
ICES-003 is very close to the FCC 47 CFR part 15 digital device emissions requirements. It is based on CSA C108.8 -M1983 test method and limits which are virtually identical to the FCC limits prior to the revision of 1989 (ie no limits above 1GHz). The test method also follows the old MP-4, but ANSI c63.4 techniques are compatible. IECS-003 is availible on the Industry Canada web site. Jon D. Curtis, PE Curtis-Straus LLC j...@world.std.com One-Stop Laboratory for EMC, Product Safety and Telecom 527 Great Roadvoice (508) 486-8880 Littleton, MA 01460 fax (508) 486-8828 http://world.std.com/~csweb On Wed, 19 Feb 1997, Vi Van (MEPCD) wrote: > Dear All, > > Does anyone have any information regarding ICES-003? > How is it different from FCC and CISPR22? > > Thanks in Advance. > > Vi Van > Mitsubishi PC >
Re:
Max, PCs have been subject to close US and German scrutiny since at least 1980. That has forced them to adopt very good shielding practices including direct connection of the shields to the cabinet in a low inpedance fashion. Anyone in the industrial controls area who needs to get up to speed on how to meet EMC requirements on products which incorporate high speed digital electronic processing capabilities should go to school on the PC on thier desk. Examining a name brand PC is one way to get up to speed on good shielding technique real fast. Is good shielding enough? If you are using digital signals - 0-5V - 1's and 0's - then it's pretty tough for the continuous RF tests to disturb you with reasonable shielding technique. ESD and EFT may still cause a problem, but usually not if the shieling is continuous. Shielding is often not enough though when trying to protect thermocouple, strain gages, or RTDs. With these devices a driving circuit applies a low level signal to the transducer and a receiving portion looks for a very small change in the resulting signal (mV) to indicate temperture rise or whatever. These receivers and drivers are typically op amp circuits with multiple stages to correct for non-linearities before the final A/D stage. These must be designed to maximize common mode rejection and their ground reference must be designed to be well behaved. A good shield will give you about 40dB of surpression and that is frequently just not enough. Jon D. Curtis, PE Curtis-Straus LLC j...@world.std.com One-Stop Laboratory for EMC, Product Safety and Telecom 527 Great Roadvoice (508) 486-8880 Littleton, MA 01460 fax (508) 486-8828 http://world.std.com/~csweb On Thu, 13 Feb 1997, Max wrote: > > Jon, > > That's great information--I also anticipate a requirement for heavy > industrial immunity in the future and have been wondering what problems I > might be in for. > > With PCs (and computers in general), isn't it the case that if the cables are > shielded and grounded to the cabinet there isn't likely to be a problem? > > For emissions, BTW, I have also had good luck with DEC. > > Max Kelson > mkel...@es.com > > > %> > %>I have tested systems to the heavy industrial immunity specification which > %>included class B PCs. Both HP Vectra computers and Dell computers faired > %>well. Ocassionally the monitors sold with these systems are disturbed to > %>the point of turning themselves off (a failure in most books). To date > %>I've always been able to solve this problem by upgrading to an NEC > %>multisync monitor. The key distinquinction of all these products is that > %>they really do meet class B by wide margins and use very good shielding to > %>get to that level. Once you have shielding that good and use digital > %>techniques inside (as opposed to small signal, high impedance analog > %>signals - thermocouples, etc.) heavy industrial immunity compliance is > %>usually a given. > %> > %>Jon D. Curtis, PE > %> > %>Curtis-Straus LLC j...@world.std.com > %>One-Stop Laboratory for EMC, Product Safety and Telecom > %>527 Great Roadvoice (508) 486-8880 > %>Littleton, MA 01460 fax (508) 486-8828 > %>http://world.std.com/~csweb > %>On Wed, 12 Feb 1997, Tony Fredriksson wrote: > %> > %>> >
RE:
I have tested systems to the heavy industrial immunity specification which included class B PCs. Both HP Vectra computers and Dell computers faired well. Ocassionally the monitors sold with these systems are disturbed to the point of turning themselves off (a failure in most books). To date I've always been able to solve this problem by upgrading to an NEC multisync monitor. The key distinquinction of all these products is that they really do meet class B by wide margins and use very good shielding to get to that level. Once you have shielding that good and use digital techniques inside (as opposed to small signal, high impedance analog signals - thermocouples, etc.) heavy industrial immunity compliance is usually a given. Jon D. Curtis, PE Curtis-Straus LLC j...@world.std.com One-Stop Laboratory for EMC, Product Safety and Telecom 527 Great Roadvoice (508) 486-8880 Littleton, MA 01460 fax (508) 486-8828 http://world.std.com/~csweb On Wed, 12 Feb 1997, Tony Fredriksson wrote: > > If such a system is not easy to find, is there any reason why one can't use > two systems to test an expansion card? > > One could be CE marked and declared for Class B ( a PC) and the > other could be a system that is CE marked and declared for Heavy > Industrial Immunity. In this way, you have shown the card to be compliant > with both standards and do not need to search for one system that has > all of the approvals. > > Is this acceptable? > > Regards, > tony_fredriks...@netpower.com > > -- > From: comp_lab > To: EMC-PSTC > Date: Wednesday, February 12, 1997 2:38PM > > Hello All, > > We are doing something out of the usual for us and have developed a product > that is a card designed to go in a PC. For our normal products, with > regards to the EMC directive, we do industrial immunity and Class B for > emissions. We would like to do the same for the PC card. The problem is I > haven't found a PC yet, that has been previously tested to the industrial > immunity standard AND class B. If anybody knows of any systems that will > pass these tests please let me know. > > Thanks for your help > > Regards, > > - > Kevin Harris > Manager, Compliance Engineering > Digital Security Controls > Toronto, Canada > 416 665-8460 Ext 378 > - >
Re: IEEE-C62.41-1991 SURGE voltages in Low-Voltage AC Power Circuits
See below. Jon D. Curtis, PE Curtis-Straus LLC j...@world.std.com One-Stop Laboratory for EMC, Product Safety and Telecom 527 Great Roadvoice (508) 486-8880 Littleton, MA 01460 fax (508) 486-8828 http://world.std.com/~csweb On Thu, 30 Jan 1997, Terry J. Meck wrote: > Hello all: > > What can you tell me about these specs.? > > IEEE-C62.41-1991 SURGE voltages in Low-Voltage AC Power Circuits * Successor to IEEE 587. Describes the surge environment. Models surges as two primary waveshape types. The unidirectional 1.2x50uS/8x20uS wave and the 100kHz ring wave. Says surges can reach 6kV (at that point the outlets arc over). Divides the enviroment into three catagories: C: outside, B: near the service entrance, A: deeper inside buidings. Says surges can reach 6kV at both A and B, but current limits A to 200A peak on the ring wave. Unidirectional surge not applied to environment A. Note that EN61000-4-5/IEC1000-4-5 adopted the unidirectional wave and applies it at lower voltages through slightly different impedances. The standard also identifies three other waveshapes which can be seen in nature and which may be appropriate for specific products. These include a long duration surge, Electrical fast transient bursts, and a slow ring wave. This standard does not set limits. It is a measurement technique standard with emphasis on the description of the environment based on decades of technical studies. > > IEEE STD 142-1991 Grounding of Industrial and Commercial Power > > IEEE STD 519-1992 Harmonic Control in Electric Power Sys. * > > IEEE STD 587-1980 electrical noise immunity spec. * The granddaddy of modern surge standards. Superceeded by 62.41 and 1000-4-5. > > Are there specified testing procedures to these * marked standards? The two I have written about ARE test proceedures. In order to apply them you need a specification of the surges levels to be applied along with a performance criteria. > > Are there EN or IEC standards that correlate to these standards? EN61000-4-5 is the direct decendent of these standards. > > With reference to noise pulses how does > IEEE-C62.41-1991 or IEEE STD 587-1980 apply the > following? To what environment or connect category? > That is to say, these wouldn't be applied to single > phase equipment @ 5A would they? Sure. But probably not at the maximum level specified in the standard. There is a neat chart in C62.41 which illustrates the number of surges in a given year at a given level which can be expected. Turns out 1kV surges are quite common. Especially if you live in Florida or Long Island where there is lots of lightning. > > High impedance 6KV amplitude with a 1.2 sec rise time and a 50 sec > duration. > > Low impedance 3KA amplitude with an 8 sec rise time and 20 sec > duration 80 joules energy. > > High impedance 6KV amplitude with a .6 sec duration at 100KHZ > > > Low impedance 500A amplitude with an .6 sec duration at 100KHZ (4 > joules energy). > > > For example the proposed specs of EN 61000-4-5 for an > industrial environment (50082-2:1995) indicate 4kVCM > and 2kV DM 1,2/50 (8/20) Tr/Th sec. > > Another question. As long as I am bringing up EN > 61000-4-5 for an industrial environment. Would it be > acceptable to specify a CE compliant external surge > suppressor for a piece of CE marked equipment that > would provide compliance to the standard when > used/required in the installation. This would move > the environment criteria would it not? You are allowed to specify the performance criteria for your equipment. If you want to tell your user in the manual that you require an external surge suppressor to be surge immune then that's OK. In effect you are telling them that if they choose not to use such a surge suppressor that the unit's performance under surge conditions is unpredictable. > > Thanks for your comments in advance. > > > Best regards, > Terry J. Meck > Senior QA/Test Engineer > 215-721-5280 > tjm...@accusort.com > Accu-Sort Systems Inc. Telford, Pa USA >
Re: Laser measuring equipment
Try GNNettest. I know they make equipment to measure lasers used in fiber optic networks. 315-797-4449. Jon D. Curtis, PE Curtis-Straus LLC j...@world.std.com One-Stop Laboratory for EMC, Product Safety and Telecom 527 Great Roadvoice (508) 486-8880 Littleton, MA 01460 fax (508) 486-8828 http://world.std.com/~csweb On Thu, 30 Jan 1997 richa...@exabyte.com wrote: > Hello all, > > Does anyone know where and who sells laser measuring equipment. > Specifically to measure the actual output of the lasers to meet the > requirements set forth by IEC 825-1 and the FDA's 21 CFR 1040.10. > > Thanks in advance. > > Richard Georgerian > Product Compliance Eng. > Exabyte > > e-mail: richa...@exabyte.com tele: 303-417-7537 fax: 303-417-7829 >
Re: How the limits determined?
You need a copy of the FCC 79-555 report and order of 1979 implementing the regulation of digital devices. Appendix C is titled "Derivation of Limit for Class B Computing Device". The class A limit was derived from CBEMA proposal CBEMA/ESC5/77/29 which was also submitted to CISPR. I would be willing to send you a copy of an exerpted FCC R&O published in Dash's 1984 annual if you send me your fax number. Jon D. Curtis, PE Curtis-Straus LLC j...@world.std.com One-Stop Laboratory for EMC, Product Safety and Telecom 527 Great Roadvoice (508) 486-8880 Littleton, MA 01460 fax (508) 486-8828 http://world.std.com/~csweb On Tue, 14 Jan 1997, Tom Bao wrote: > Can anyone give me some background or history information on how the > radiated and conducted emission limits were determined by FCC and CISPR, in > terms of the field strength level? Any research supports the limit level? > Any input will be greatly appreciated. > > Regards, > Tom > http://www.rcic.com >
Re: Measurement Uncertainty
Dear Hans, I know of no manufacturers actually engaged in series production audits. So lets hear from them. Please respond to this forum. The companies I work with look to CISPR 22 8.2.1.1 and test one sample. Some of them are happy with 0dB margin. I advise a higher margin, but they are responsible for signing the DoC. To date it would appear to me that the 80/80 rule only has a place in making it harder to take product off the market. You can go to market with only one sample tested, but if someone wants to restrict your access they have to perform an 80/80 rule statistical test to say you fail (CISPR 22 8.2.4). As a test lab, I'd love the 80/80 rule if the market would support it (three-five times the testing, yippee!). The doctrine also seems to need a bit of clarification: Xn is refered to as the value of the individual item. Is this the value of the one point closest to the limit? Can you change the frequency? On a product do you evaluate more than one frequency? How many? - the six closest to the limit? When doing more than one test, are several 80/80 tests performed - one for radiated, one for conducted? The 80/80 test is a statistician's dream and a test engineer's nightmare. Jon D. Curtis, PE Curtis-Straus LLC j...@world.std.com One-Stop Laboratory for EMC, Product Safety and Telecom 527 Great Roadvoice (508) 486-8880 Littleton, MA 01460 fax (508) 486-8828 http://world.std.com/~csweb On Mon, 13 Jan 1997 hans_mellb...@non-hp-santaclara-om4.om.hp.com wrote: > > I take exception with the statement "passing is passing and failing is > failing". CISPR 16 and 22(section 8.2.4) (maybe others too) require that > during manufacturing sampling, the products pass the so called 80/80 rule. > A minimum sampling of 3 units is required to perform this 80/80 calculation > and products with minimal margin will discover that they fail the formula > test! Go ahead and try a sample hypothetical test! > > > __ Reply Separator > _ > Subject: Re: Measurement Uncertainty > Author: Non-HP-owner-emc-pstc (owner-emc-p...@majordomo.ieee.org) at > HP-Boise,mimegw2 > Date:01/13/97 05:14 AM > > > In the USA, NIST has published Technical Note 1297 1994 ed. "Guidelines > for Evaluating and Expressing the Uncertainty of NIST measurement > results." > > Our NVLAP accreditation requires us to estimate uncertainties in our test > reports. Every Curtis-Straus EMC or Telco test report contains > uncertainty > estimates. As to the passing margin, passing is passing and failing is > failing. Before you take measurement uncertainty into the limit, first > consider that technique has improved (and therefore unceratinty is lower) > than it was when the limits were formulated. Second consider that the > regulators which accepted the limit were well aware that uncertainty > exists and in all likelyhood accounted for it in their choice of the > limit. > > That said, I advise all clients who are within our uncertainty of the > limit (but passing), that they should be aware that they may fail next > time. > If they are at the prototype stage, or building a product which will > become the platform for future development, it is advisable to seek a > larger margin. > > Jon D. Curtis, PE > > Curtis-Straus LLC j...@world.std.com > One-Stop Laboratory for EMC, Product Safety and Telecom > 527 Great Roadvoice (508) 486-8880 > Littleton, MA 01460 fax (508) 486-8828 > http://world.std.com/~csweb > On Fri, 10 Jan 1997, Barge, Michael wrote: > > > > > > > FROM: michael_ba...@atk.com > > > > Item Subject: Measurement Uncertainty > > > > Greeting Tregers; > > > > There seems to be a requirement that, when giving a measured value, there > > must be an uncertainty associated with that value describing the confidence > > of that value. > > > > (1) Do most labs report an uncertainty measurement in the test report, on > > the data sheet, on a certificate of compliance? > > (2) How did you generate the measurement of uncertainty for emission > > tests? For immunity tests? > > > > AND MOST IMPORTANTLY > > > > (3) What do you tell the customer when he is below the limit by less than > > the measurement uncertainty? When he is above by less? > > > > J Michael Barge > > Alliant Techsystems > > Annapolis, MD > > >
Re: Measurement Uncertainty
Response to Tony Fredriksson's comments: See below. Jon D. Curtis, PE Curtis-Straus LLC j...@world.std.com One-Stop Laboratory for EMC, Product Safety and Telecom 527 Great Roadvoice (508) 486-8880 Littleton, MA 01460 fax (508) 486-8828 http://world.std.com/~csweb On Mon, 13 Jan 1997, Tony Fredriksson wrote: > > Jon, > > Thanks for the info on the NIST Technical Note. Looks like I need > to get a copy and undertand it. > > It is good to know that Curtis-Straus estimates uncertainty. > I am particularly interested in the EMC side of the discussion > and have a couple of questions: > > 1. In the case of Immunity, I suppose the lab would only be able > to estimate uncertainty of the disturbance from the test generator. > Is that correct? Wouldn't the loading of the signal source from > EUT have a dramatic affect on the test result uncertainty? If this > is the case, how is it factored in such that uncertainty of the end > result is quantified to any practical degree? For radiated immunity, we do a Type B uncertainty evaluation on the test. We only consider the factors from the test equipment as we feel our uncertainty results from the level of the field without the EUT. The effects of the EUT on the field will vary by EUT (size, dimensional resonances, etc.) but between samples of individual EUTs these factors should be well behaved. We do ignore cable position as a factor, relying on the fact that we test 4 different sides in two polarities to give us some statistical protection in this area. The major contribution to uncertainty then becomes the leveling of the field which is +-3dB. Since this is a MUST be within 0dB to 6bB, we use Uj as 3dB and divide it by square root of three assuming a rectangular distribution. See the NIST note. > > 2. In the case of EMI, what is the range of uncertainty that one of > your tests can provide? I would think it is a function of frequency. > Does it attempt to take into account the uncertainty due to a change > in cable or preripheral placement from one setup to the next of the > exact same EUT? If so, how was that uncertainty derived? It could be a function of frequency. Certainly antenna factors and site anomalies are generally better behaved above 200MHz. To date we use a simple uncertainty using estimated worst case results across the frequency spectrum. As factors we have: antenna factor: +-1dB, NSA: +-4dB (ours is really max 2dB so we use +-4dB, but assume a traingular distribution on this factor), Equipment factors: SA flatness 1.5dB, cable calibration: .3dB, test method variance (cable manipulation: +-2dB, normal distribution). Add it up using Root-sum-of-squares=2.9dB uncertainty: Note that there are additional factors based on the assumed distributions of the uncertainties. > > The reason that I am curious about this is that I have seen some cables > so hot (headphone on a CD ROM port for example) that moving them an > inch or two in either direction can vary emissions by 10dB or more. That > would seem to be quite unpredicatable by statistical methods and would > seem to dwarf any uncertainties from other sources. This even considers > test setup methods that have been designed to minimize test variation > (such as ANSI C63.4). Yes, cable manipulation done properly is still the over-riding factor in repeatibility. I am able to obtain 2dB repeatibility with attention to cable manipulation to maximize emissions at each frequency. If you don't maximize the cables you will see variances of at least 10dB between EUT setups that appear identicle. > > I can see that using the lab's stated uncertainty in combination with > a CISPR 16 style sampling test would be a significant improvement over > other procedures. > > Thanks, > tony_fredriks...@netpower.com > > -- > From: Jon D Curtis > To: Barge, Michael > Cc: 'emc-p...@ieee.org' > Subject: Re: Measurement Uncertainty > Date: Monday, January 13, 1997 9:14AM > > In the USA, NIST has published Technical Note 1297 1994 ed. "Guidelines > for Evaluating and Expressing the Uncertainty of NIST measurement > results." > > Our NVLAP accreditation requires us to estimate uncertainties in our test > reports. Every Curtis-Straus EMC or Telco test report contains > uncertainty > estimates. As to the passing margin, passing is passing and failing is > failing. Before you take measurement uncertainty into the limit, first > consider that technique has improved (and therefore unceratinty is lower) > than it was when the limits were formulated. Second consider that the > regulators which accepted the limit were well aware that uncertainty > exists and in all likelyhood accounted f
Re: Measurement Uncertainty
In the USA, NIST has published Technical Note 1297 1994 ed. "Guidelines for Evaluating and Expressing the Uncertainty of NIST measurement results." Our NVLAP accreditation requires us to estimate uncertainties in our test reports. Every Curtis-Straus EMC or Telco test report contains uncertainty estimates. As to the passing margin, passing is passing and failing is failing. Before you take measurement uncertainty into the limit, first consider that technique has improved (and therefore unceratinty is lower) than it was when the limits were formulated. Second consider that the regulators which accepted the limit were well aware that uncertainty exists and in all likelyhood accounted for it in their choice of the limit. That said, I advise all clients who are within our uncertainty of the limit (but passing), that they should be aware that they may fail next time. If they are at the prototype stage, or building a product which will become the platform for future development, it is advisable to seek a larger margin. Jon D. Curtis, PE Curtis-Straus LLC j...@world.std.com One-Stop Laboratory for EMC, Product Safety and Telecom 527 Great Roadvoice (508) 486-8880 Littleton, MA 01460 fax (508) 486-8828 http://world.std.com/~csweb On Fri, 10 Jan 1997, Barge, Michael wrote: > > > FROM: michael_ba...@atk.com > > Item Subject: Measurement Uncertainty > > Greeting Tregers; > > There seems to be a requirement that, when giving a measured value, there > must be an uncertainty associated with that value describing the confidence > of that value. > > (1) Do most labs report an uncertainty measurement in the test report, on > the data sheet, on a certificate of compliance? > (2) How did you generate the measurement of uncertainty for emission > tests? For immunity tests? > > AND MOST IMPORTANTLY > > (3) What do you tell the customer when he is below the limit by less than > the measurement uncertainty? When he is above by less? > > J Michael Barge > Alliant Techsystems > Annapolis, MD >
Re: UL Surge generator
What you want is an old keytek generator. I checked their 3/96 price list and it looks like they don't make a module for their new ECAT system. The UL waveshape really is a relic from the dawn of the surge simulation game. It uses generation techniques that are basically incompatible to a large extent with modern surge generators. If you can't find the keytek gear, before I left CDI I designed a plugin set for their M5 surge generator which mimicks the surge envelope with two modern plugin designs. Not perfect, but it may be the best you can get. Keytek 508-657 4803 CDI 508-264-4668 Jon D. Curtis, PE Curtis-Straus LLC j...@world.std.com One-Stop Laboratory for EMC, Product Safety and Telecom 527 Great Roadvoice (508) 486-8880 Littleton, MA 01460 fax (508) 486-8828 http://world.std.com/~csweb On Wed, 8 Jan 1997, Kevin Harris wrote: > Hi, > > Does any one know of a good surge generator that generates the UL surge > waveform? UL requires that a " transient waveform at 2400V shall have a > pulse rise time of 100 V per microsecond, a pulse duration of 80 > microseconds, and an energy level of 1.2 joules. Other applied transients > shall have peak voltages representative of the entire range of 100 to 2400 > volts (typically 100V, 500V, 1000V & 2400V) with pulse durations from 80 > microseconds to 110 microseconds, and an energy level not less than 0.3 > joules or greater than 1.2 joules" > > Thanks for your help > > Regards, > > - > Kevin Harris > Manager, Compliance Engineering > Digital Security Controls > Canada > 416 665-8460 Ext 378 > - >
Re: HELP: EMI - CFR 47 Exemption for Machine Controls ?
Dear George, Look in 47 CFR 15.103 Exempted Devices. You are refering to section (b) exempted from the technical requirements of part 15 are "digital devices used exclusively as an electronic control or power system utilized by a public utility or in an industrial plant..." Jon D. Curtis, PE Curtis-Straus LLC j...@world.std.com One-Stop Laboratory for EMC, Product Safety and Telecom 527 Great Roadvoice (508) 486-8880 Littleton, MA 01460 fax (508) 486-8828 http://world.std.com/~csweb On Tue, 7 Jan 1997 hans_mellb...@non-hp-santaclara-om4.om.hp.com wrote: > Check 47 CFR part 2 sections 803, 805, 806, 807 and 809. Essentially if your > ISM equipment is classified as a "radio frequency device" or "digital device" and not selling to the US goverment you must comply with the technical requirements of part 15, or part 18. Part 18 section 121 allows for exemptions for certain ultrasound and MRI equipment. Other than that, I'm certain you have to comply! Best Regards, Hans Mellberg __ Reply Separator _ Subject: HELP: EMI - CFR 47 Exemption for Machine Controls ? Author: Non-HP-owner-emc-pstc (owner-emc-p...@majordomo.ieee.org) at HP-Boise,mimegw2 List-Post: emc-pstc@listserv.ieee.org Date:01/06/97 04:33 AM Dear Compliance Collegues CFR47 sets emission limits for digital devices. As far as I know there is or there was an exemption for machine controls, i.e. there are no emission limits for industrial machines ( I am not referring to ISM as defined by 47CFR18) I can not find this exemption in the 1993 edition of the CFR 47. Can anybody point me the ºº of CFR where this exemptions or was mentioned ? Thanks in advance George * Dr. Georg M. Dancau* HAUNI MASCHINENBAU AG * * g.m.dan...@ieee.org* EMC Lab * * TEL: +49 40 7250 2102 * Kampchaussee 8..32 * * FAX: +49 40 7250 3801 * 21033 Hamburg, Germany * * home: Tel: +49 40 738 51 07* Lohbruegger Landstr. 82 * * Fax: +49 40 730 11 99* 21031 Hamburg, Germany *
Medical Device Discussion Group
I thought TREG is such a good idea for telecom devices, why not one for medical device regulatory information? Thus MEDIC, the MEdical Devices Information Consortium ... to subscribe send "subscribe medic" to majord...@world.std.com. To contribute, members may send messages to me...@world.std.com. Info on MEDIC: Welcome to the home of me...@world.std.com, the Medical Devices Information Consortium, an established discussion group on medical devices regulations. Medical Devices Information Consortium (MEDIC) == Charter and Guidelines 10 December 1996 MEDIC is an informal group of people interested in medical device regulations and standards world-wide, networked electronically by mailing list. Its purpose is to provide a forum for the sharing of public, but esoteric or possibly obscure medical device compliance information, or related information with limited natural distribution. Members need only send contributions to: me...@world.std.com All mail sent to this Internet address will be immediately echoed to everyone on the MEDIC list by an automated list server. SUBSCRIBING OR UNSUBSCRIBING - Send an Internet e-mail request with the phase "subscribe medic" or "unsubscribe medic" in it to: majord...@world.std.com DISCLAIMER: MEDIC postings are the sole responsibility of the message originators. Jon Curtis does not assure the correctness or viability of any information distributed by the MEDIC list server, nor accepts any responsibility for the use of any MEDIC distributed information. MESSAGE CONTENT GUIDELINES: 1. Correspondence should be limited to information or queries relating to medical device regulations or standards only. Shared information should not be confidential or in any way proprietary. Please don't use the MEDIC for simple correspondence - Private correspondence should be addressed directly, unless it has broad appeal or interest. 2. Blatant or overt advertising of goods or services is not permitted. The MEDIC list server is provided as a service by Jon Curtis, whose policies prohibit anything that might be construed as conflict of interest. Exceptions: a) Short, non-promotional "trailers" or signature lines for the sole purpose of identifying the sender and the sender's organization. b) Answers to queries about goods or services, where the intent of the answer is to inform, but not promote. (When in doubt, send the questioner a private message.) c) This guideline is specific to the use of the MEDIC list server, and in no way inhibits individuals from contacting MEDIC members privately and independently. 3. Posting of medical device job openings is OK so long as they are short (i.e., 1 paragraph), non-commercial (no agencies or headhunters - no fees involved), infrequent (about one out of every 10 messages or less), and contain an off-MEDIC contact name and phone number or e-mail address. Same goes for jobs-wanted (if you can fit your resume into one paragraph!). 4. Using key words in the title or subject line will assist members who archive the message traffic and may wish to search it later. Suggested keywords include: CUSTOMIZED or DIAGNOSTIC or a country name (where the information is country-specific). 5. Queries or requests for information should be focused and brief. Respondents should be careful about endorsements - When in doubt, don't. HISTORY: MEDIC was started by Jon Curtis at Curtis-Straus LLC on 8 December 1996. QUESTIONS?: Send email to Jon Curtis at: medic-ow...@world.std.com Jon D. Curtis, PE Curtis-Straus LLC j...@world.std.com One-Stop Laboratory for EMC, Product Safety and Telecom 527 Great Roadvoice (508) 486-8880 Littleton, MA 01460 fax (508) 486-8828 http://world.std.com/~csweb
RE: EU Modem Approvals
From: "Rene Debets" Message-Id: To: t...@world.std.com Subject: RE: EU Modem Approvals Dear Duane, No, it's not legal to use a modem in any other country than the one it is approved for. It doesn't even matter whether it does happen to meet the requirements Best regards, Rene -- From: treg-appro...@world.std.com on behalf of Duane J Marcroft Sent: Thursday, September 19, 1996 10:29 PM To: t...@world.std.com Subject:EU Modem Approvals Hi Treg'rs I have a question, if anyone could answer it I would appreciate it. I know rsNTR 21 has not been approved. But, if I design the DAA per NET 4 or rsNTR 21 for say the U.K. is it legal to use the modem in any other country? I'm not asking if it can sold in any other country, just if it can be legally carried to another EU country and used. I've read the verbage dealing with this point, but I'm still not clear if this the case. Thank you in advance. Regards, Duane Marcroft Telecom Consultant
1996 copy of the EMC directive guidelines
Try Conformity Standards at (508) 486-8880 for a copy of the 1996
guidelines.
Jon D. Curtis, P.E.
Curtis-Straus LLCphone: (508) 486-8880
527 Great Road fax:(508) 486-8828
Littleton, MA 01460 email: j...@world.std.com
USA
On Tue, 13 Aug 1996 ron_well...@hp-paloalto-om4.om.hp.com wrote:
> ...
>
> Item Subject: CE marking of components
> Howdy Lyle,
>
> How does one get a complete copy of the 1996 guidelines?
>
> Regards,
> Ron Wellman
> well...@corp.hp.com
>
>
> __ Reply Separator
> _
> Subject: CE marking of components
> Author: Non-HP-owner-emc-pstc (owner-emc-p...@majordomo.ieee.org) at
> HP-PaloAlto,shargw3
> Date:8/13/96 7:38 AM
>
>
> The best guidance on CE marking of components for the EMC Directive is
> included in the 1996 revision of the "Guidelines on the application of
> council directive 89/336EEC.." If you dont' have a copy, you need to
> get one.
>
> The guidelines include over three pages of discussion relating to
> application of the EMC Directive to components. The key point is that
> components do not need to comply with the directive unless they are placed
> on the market for distribution and use AND perform a direct function.
> Direct function means any function which meets the needs of a user and can
> be directly used by such a user, without the need to make any further
> adjustments other than any connection essential for its electrical power
> supply or for the exchange of analogue or digital signals.
>
>
> Lyle Luttrell
> TUV Product Service
>
>
> The following was included as an attachement. Please use UUDECODE
> to retrieve it. The original file name was 'ATTRIBS.BND'.
>
>
> ...
>
> Item Subject: ATTRIBS.BND
> Could not convert BINARY FILE item to text.
> Will attempt to 'shar' item as file '08snsp1' at end of msg.
>
>
> # This is a shell archive. Remove anything before this line,
> # then unpack it by saving it in a file and typing "sh file".
> #
> # Wrapped by David Fritsch on Tue Aug 13 16:55:28 1996
> #
> # This archive contains:
> # 08snsp1
> #
> # Error checking via wc(1) will be performed.
>
> LANG=""; export LANG
> PATH=/bin:/usr/bin:$PATH; export PATH
>
>
> rm -f /tmp/uud$$
> (echo "begin 666 /tmp/uud$$\n#;VL*n#6%@x\n \nend" | uudecode) >/dev/null 2>&1
> if [ X"`cat /tmp/uud$$ 2>&1`" = Xok ]
> then
> unpacker=uudecode
> else
> echo Compiling unpacker for non-ascii files
> pwd=`pwd`; cd /tmp
> cat >unpack$$.c <<'EOF'
> #include
> #define C (*p++ - ' ' & 077)
> main()
> {
> int n;
> char buf[128], *p, a,b;
>
> scanf("begin %o ", &n);
> gets(buf);
>
> if (freopen(buf, "w", stdout) == NULL) {
> perror(buf);
> exit(1);
> }
>
> while (gets(p=buf) && (n=C)) {
> while (n>0) {
> a = C;
> if (n-- > 0) putchar(a << 2 | (b=C) >> 4);
> if (n-- > 0) putchar(b << 4 | (a=C) >> 2);
> if (n-- > 0) putchar(a << 6 | C);
> }
> }
> exit(0);
> }
> EOF
> cc -o unpack$$ unpack$$.c
> rm unpack$$.c
> cd $pwd
> unpacker=/tmp/unpack$$
> fi
> rm -f /tmp/uud$$
>
> echo x - 08snsp1 '[non-ascii]'
> $unpacker <<'@eof'
> begin 660 08snsp1
> M0F5Y;VYD(%!A8VME9"!!='1R:6)U=&5S +0514* 0T4@;6%R:VENX
> M9R!O9B!C;VUP;VYE;G1SX
> MX
> M $QY;&4@3'5T=')E;&P X
> M !9534Y*W5"-S)MX
> M0F5Y;VYD(%!R;W!R:65T87)Y($1A=&$: !$ ! #UX
> M P 5&5X=#H#5&AE(&)E M;VX@0T4@;6%R:VEN9R!O9B!C;VUP;VYE;G1S(&9O M=&EV92!I M(")'=6ED96QI;F5S(&]N('1H92!A<'!L:6-A=&EO;B!O9B!C;W5N8VEL(&1IX
> M6]U(&1O;G0G(&AA=F4@X
> M82!C;W!Y+"!Y;W4@;F5E9"!T;R!G970@;VYE+B @"@I4:&4@9W5I9&5L:6YEX
>
Stripped email addresses
Dear treggers, Most of you know that treg switched over to an automated mail server last April. Stripped email addresses are a consequence of that. With an automated server run open loop it will get into a loop every so often and fill all subscriber's boxes with 300 messages. For instance whenever one of you goes away I get 10 messages a day back from you saying that you are on vacation or whatever. If I didn't have some controls in place 350 people would hear about your vacation 1000 times a day as these messages looped back on themselves. For the most part sending the message from treg-approval rather than treg catches most bounced messages. Ocassionally some beserk server truncates this to just treg and then there's trouble. To catch the majority of these I have treg set so that only members of the list can post to treg automatically. If your email address is not on the list, you have to wait till I read my email and manually forward your message to treg - this process also makes the email come from me, but I keep your address as the first line of the message. Don't like it? Change your email address on treg to your real email address, rather than whatever marketing driven email alias you currently have on treg. Then when treg checks your email address against the list, you'll be on it and your message will be automatically forwarded to the membership without me typing a character. As long as you keep having treg deliver to your alias , your postings will be delayed and they will appear to originate from me. To fix your address send: subscribe treg johnsm...@realaddress.com unsubscribe treg johnsmith@big_marketing_ploy.com end to: majord...@world.std.com Thank you, Jon D. Curtis, P.E. Curtis-Straus LLCphone: (508) 486-8880 527 Great Road fax:(508) 486-8828 Littleton, MA 01460 email: j...@world.std.com USA
Re: HP App Note
App note number on the front cover is 1273, but if you call HP they probably will not be able to track it by that... You need the number off the rear cover: 5964-1917E. I don't know about the web site. Try the plain ol' phone at 1 800 452 4844. Jon D. Curtis, P.E. Director of Engineering email: j...@world.std.com Curtis-Straus LLCphone: (508) 486-8880 527 Great Road fax:(508) 486-8828 Littleton, MA 01720 http://world.std.com/~jdc/ USA On Mon, 24 Jun 1996 j...@bangate.compaq.com wrote: > Good Morning, > > I recently saw in a trade magazine an announcement that Hewlett Packard had > an app note avaliable that dealt with designing and measuring power > supplies to the requirements of IEC 555 (harmonics, fluctuations etc.). > Does anyone know the app #, and if it is avaliable from HP via it's www > page ? > > Thanks all, > > > Jerry F. >
Specs for Brazil, Mexico
From: rgu...@anonymous.com Subject: Specs for Brazil, Mexico Suggest you contact Certelecom Laboratories by phone or fax or E-Mail with what you want. They have a library of standards and approval forms. Apparently this includes the standards for Mexico and Brazil. Certelecom is a member of the CCT committees for NAFTA and holds the chair of the conformity Assessment Group. Phone is 1-800-563-6336, Fax is 1-613-737-9691. They have a home page on Internet and are a division of the British test lab KTL. RCIC Guest rgu...@anonymous.com Courtesy of RCIC http://uc.com/compliance_engineering/
Re: More on Competent Bodies
See below. Jon D. Curtis, P.E. Director of Engineering email: j...@world.std.com Curtis-Straus LLCphone: (508) 263-1897 409 Massachusetts Avenue fax:(508) 263-4164 Acton, MA 01720 http://world.std.com/~jdc/ USA On 5 Jun 1996, rbusche wrote: > For some reason, it is still unclear in my mind the role of a competent body > in the big picture. I have thrown out several topics for discussion on this, > yet, the answer still somewhat eludes me. Please bear with me as I ask this > question one last time. > > If company A in Europe buys a product from company B in the US, and the > product is delivered with a CE Mark on the device(s). (Of course with the DoC > accompanying the mark). Shouldn't company A be allowed to determine if the > equipment suits them for their application AND shouldn't company A be able to > accept whatever equipment they want WITHOUT a competent body involved? Yes, but... for emissions they must choose an approved standard. This is to prevent interference to a third party (company C) outside the transaction. For immunity, a standard must also be picked. BUT, company A could accept that Company B writes in it's manual that the product's performance is unknown and possibly horrible under ESD, EFT, RFI, etc. (why company A would accept substandard immunity is still an issue) Remember, under the performance criteria of the generic immunity documents, Company B is representing that their product performs as specified in the manual under EMC disturbances. The immunity side of the EMC directive can be looked at as setting up a covenant between the transacting parties. In the absense of further agreements, Company A has reason to believe that Company B's product operates as stated in the manual under a suite of electromagnetic disturbances defined by the standards as applicable to the expected end-use environment. >I > understand that if no standard exists or has been officially published in the > OJ, a competent body might be useful. Right. But there are currently very few areas under the EMC directive that are not covered by the standards route. In fact, since the generic documents for immunity and emissions are published there is always a standards route to compliance. Only where the standards route is particularly onerous and you can convince a competent body to go easier on you, does the TCF route for the EMC directive make any economic sense at all. In my experience, rather than interpreting EMC regulations in a rational manner to minimize the required testing, competent bodies tend to test to everything they can find that might be applicable including draft standards not yet even published! >But in my scenario, I am providing ITE > equipment to a larger system which is arguably in this gray area. If your customer says you need to go the TCF and you can't convince him otherwise, you'll need a TCF to get the sale. Make sure he pays for it! > > Even here I have some concerns. The final application is a flight simulator > with hydraulic motion platforms, displays, and computer systems. It is not > obvious to me that this is justification for hiring a competent body to > evaluate EMC performance. The only justification is based on your customer's lack of trust in you or the lab you contract to do the testing. There is no requirement in law for you to get a TCF from a competent body. > > The issue of "light" industrial Vs "heavy" industrial in my mind is one of > ruggedization for the effects of EMC. Given that EN55022 defines the > environment for a Class A emission device, the generic immunity standard > EN50082-X should be a customers decision. This is a non-issue as relates to competent bodies. The standards route is open for both light and heavy industrial products. I agree that you should be able to pick either or as long as you document your decision in your specifications to the customer. You are responsible for defining the environment in which you intend your product to be used. > > Please excuse me if this is a dumb question, but if someone can shed a bit > more light I promise to shut up on this issue. > > Thanks in advance > > > Rick Busche > rbus...@es.com >
Re: Power Factor Correction, Medical Equipment?
Standards are published in the OJ for use with a particular directive. In this case EN 61000-3-2 and EN 61000-3-3 have been published in the OJ as standards used to conform to the EMC directive. If you choose to meet the Medical Devices Directive (Watch out that you are within it's scope!) now, then you do not have to meet these harmonic standards until they are published in the OJ under the Medical Devices Directive. Currently EN 60601-1-2 is the only EMC document listed in the OJ to date for the Medical Device Directive. It has this to say on Low Frequency emissions: 36.201.2.1 VOLTAGE FLUCTUATIONS and harmonic distortion No requirements for EQUIPMENT and/or SYSTEMS. On the other hand, you may choose to pursue your approvals under the existing national schemes until June 15 1998. In that case you would need to meet the EMC directive now and technically you would need to meet the harmonic emissions standard EN 61000-3-2. I say technically because CENELEC postponed the mandatory date for EN61000-3-2 til June 1, 1998 but Brussels refused to publish the ammendment in the OJ leaving it up to national governments to delay their enforcement of EN61000-3-2 if they so choose. See previous discussions of the harmonic standards for more background information on EN61000-3-2. Jon D. Curtis, P.E. Director of Engineering email: j...@world.std.com Curtis-Straus LLCphone: (508) 263-1897 409 Massachusetts Avenue fax:(508) 263-4164 Acton, MA 01720 http://world.std.com/~jdc/ USA On Fri, 31 May 1996 littlew...@aol.com wrote: > Although you are correct - neither does the EMC Directive. BUT the EN for > harmonics IS in the OJ and it would seem to me to be applicable. Any one else > agree?? >
Re: Dates on MDoC
The requirement for date coding the Declaration of Conformity (DoC) under the Low Voltage Directive is contained in Directive 93/68/EEC. This directive modifies the CE marking scheme contained in many directives and adds CE marking to the Low Voltage Directive 73/23/EEC. For the Low Voltage Directive specifically, it adds, "The EC declaration of conformity must contain the following elements: -the last two digits of the year in which the marking was affixed." I think your reading material may be a little confused. The declaration of conformity applies to a single item of your production. Therefore the date on it will change as different units of the product are marked at diferent times. Thus consumer confusion as to which standards were used to approve the product should be minimized as the standards applied will always be those in force when the CE marking is applied. Unless your distribution channel is years long, the consumer will always be getting product with a current date on it. Jon D. Curtis, P.E. Director of Engineering email: j...@world.std.com Curtis-Straus LLCphone: (508) 263-1897 409 Massachusetts Avenue fax:(508) 263-4164 Acton, MA 01720 http://world.std.com/~jdc/ USA On Fri, 26 Apr 1996 w...@dolby.com wrote: > Folks, > > Various bits of literature I have here state that, with respect > to the LVD, our Declaration of Conformity must show the year that > the CE mark was first applied to the product. > > Can anyone tell me where in the official documents this is shown > as a requirement? > > Seems to me that this could be confusing to a customer if the > standards are changed/or updated. > > Thanks in advance, > > Bill Wray > Dolby Labs > San Franciso > >
Re: FCC 47 CFR & Indust Equip
Section 15.103(b) CFR 47 (Exempted devices) exempts "A digital device used exclusively as an electronic control or power system" ... "in an industrial plant" from complying with the technical requirements of Subpart B. This means you don't have to do any testing and you do not need to label your product. You are however still subject to Part 15, specifically section 15.5 which requires you to correct any interference to licensed radio transmissions that your product causes in the field. Also, under section 15.29 you will need to comply with any commission request to evaluate your product (extremely unlikely, bordering on winning the lottery without betting). The legal issues aside, you may still wish to test your products for marketing reasons. You may find compliance with the FCC limits to be a selling feature for your equipment. If you are meeting the European requirements, compliance with the FCC limits should be almost automatic, in fact the same test data can usually used to show compliance with both the FCC and European specs. Finally, the FCC reevaluates the exemptions on about a ten year cycle. Right now they "recommend" that your class of products comply with the technical requirements. Someday the FCC might extend coverage to your equipment. Jon D. Curtis, P.E. Director of Engineering email: j...@world.std.com Curtis-Straus LLCphone: (508) 263-1897 409 Massachusetts Avenue fax:(508) 263-4164 Acton, MA 01720 http://world.std.com/~jdc/ USA On Wed, 24 Apr 1996 m_sher...@delphi.com wrote: > We're a manufacturer of industrial equipment. The equipment > goes into what the European EMC directive would classify as a > heavy industrial environment. We use a lot of electronics--PCs, > PLCs, sensors, etc--in our controls that are built into this > equipment. > > Question: do we have to comply with the FCC regs, Title 47 CFR > 15, subpart A (b), as an unintentional radiator? > > thanks! > Mike Sherman > Product Safety Engineer > FSI International > (612) 361-8140 > m_sher...@delphi.com >
Re: FCC Website Information
As to item 2 on the part 68 leakage test: It is a highpot type test. The idea is to see if hazardous currents from the AC power mains can reach the telco interface. The isolation is tested in two places: Once by placing 1000VAC between Tip/Ring and a long list of other parts of the product (which in most cases can be simplifed to logic ground). Second by placing 1500VAC between the AC mains inlet and a somewhat shorter list of parts of the product (also generally simplified to logic ground). In each case no more than 10mA of current can flow. The voltage is ramped to peak over 30 seconds and then maintained for another 60 seconds. Note that intentional paths to ground such as MOVs and spark gaps are removed for the test. If you have more questions or desire greater detail please feel free to call. Jon D. Curtis, P.E. Director of Engineering email: j...@world.std.com Curtis-Straus LLCphone: (508) 263-1897 409 Massachusetts Avenue fax:(508) 263-4164 Acton, MA 01720 http://world.std.com/~jdc/ USA On Wed, 24 Apr 1996, Larry Merchell wrote: > > 1. For Everyones Information, > > CFR's can be downloaded from (via Netscape): > > Federal Communication Commission > Office of Engineering and Technology > FCC Rules and Regulations > > located at: > http://www.fcc.gov/oet/info/rules/ > > 2. I am looking for information regarding 47 CFR 68.304 "Leakage current > limitations". The standard states that the leakage current must be less > that 10mA at 1500VAC from AC line to case [ (b) to (c) ], which looks like a > Hipot test not a leakage test. Does anyone have any additional information > regarding this? > > > Thank you for any help. > > Larry Merchell > Product Safety Engineer > Xentek Power Systems > > lar...@electriciti.com >
