PC power supply with PFC
Dear Colleagues, I appreciate if you could help me with my problem please. We use PC power supply in our control machine for feeding our motherboard. The end product is intended for EU. I am unable to locate a PC power supply with PFC and all the vendors that I have approached say to me it is not needed. My question in particular to those of you who work in PC industry is what is the situation with PC power supplies as far as PFC is concerned? Are there are PC power supply with PFC around? Many thanks Peter --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: 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,"
RE: 120V appliance on 240V supply
This is a micro-wave right? This could explain why my wife burns my eats! (Please don't call her I have enough grief already) Gary -Original Message- From: Price, Ed [mailto:ed.pr...@cubic.com] Sent: Monday, May 14, 2001 1:57 PM To: emc-p...@ieee.org Subject: RE: 120V appliance on 240V supply Although this is not a safety concern, the timer may have it's clock derived from the powerline frequency. That would make the clock, and the timer function, run slow on 50 Hz. Regards, Ed Ed Price ed.pr...@cubic.com Electromagnetic Compatibility Lab Cubic Defense Systems San Diego, CA USA 858-505-2780 (Voice) 858-505-1583 (Fax) Military & Avionics EMC Services Is Our Specialty Shake-Bake-Shock - Metrology - Reliability Analysis >-Original Message- >From: wo...@sensormatic.com [mailto:wo...@sensormatic.com] >Sent: Monday, May 14, 2001 9:18 AM >To: emc-p...@ieee.org >Subject: RE: 120V appliance on 240V supply > > > >If the frequency rating of the product is 50-60 Hz, it should be OK. >However, if the rating is only 60 Hz, there may be the >following frequency >sensitive concerns: > >* Lower output from transformers due to insufficient core size >* Slower speed fans causing cooling problems (if ac fans) >* Higher ripple currents in the rectification filter >capacitors may >increase causing higher internal temperatures which will lead >to lower life >* Lower dc output from capacitor input rectification filter >* Decreased low-line tolerance > >Richard Woods > > -- > From: Ravinder Ajmani [SMTP:ajm...@us.ibm.com] > Sent: Monday, May 14, 2001 11:49 AM > To: emc-p...@ieee.org > Subject: 120V appliance on 240V supply > > > > Hi, > I am interested in knowing if a 120V, 60Hz microwave oven can be >safely > used on a 240V, 50Hz mains supply with a step-down transformer. > > Regards, Ravinder > > Email: ajm...@us.ibm.com > >*** > > Always do right. This will gratify some people and astonish the >rest. > Mark Twain --- 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 searchable on the web at: http://www.rcic.com/ click on "Virtual Conference Hall,"
Re:120V appliance on 240V supply
Ravinder, Yes, been there, done that! (Kenmore 1980's Model). Used a 2kVA xformer w/ US style outlet strip for microwave and other US kitchen appliances. Only problem - Clock/Timer ran at 5/6 time so it was necessary to enter 1:12 for every 1 minute of cook time! (Perhaps some up to date models run clock from a crystal so wouldn't have that problem). Tony Firth,Electrical Eng., Quester Technology Inc.,Fremont,CA Reply Separator Ravinder Ajmani wrote: <... knowing if a 120V, 60Hz microwave oven can be safely 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,"
RE: 120V appliance on 240V supply
Although this is not a safety concern, the timer may have it's clock derived from the powerline frequency. That would make the clock, and the timer function, run slow on 50 Hz. Regards, Ed Ed Price ed.pr...@cubic.com Electromagnetic Compatibility Lab Cubic Defense Systems San Diego, CA USA 858-505-2780 (Voice) 858-505-1583 (Fax) Military & Avionics EMC Services Is Our Specialty Shake-Bake-Shock - Metrology - Reliability Analysis >-Original Message- >From: wo...@sensormatic.com [mailto:wo...@sensormatic.com] >Sent: Monday, May 14, 2001 9:18 AM >To: emc-p...@ieee.org >Subject: RE: 120V appliance on 240V supply > > > >If the frequency rating of the product is 50-60 Hz, it should be OK. >However, if the rating is only 60 Hz, there may be the >following frequency >sensitive concerns: > >* Lower output from transformers due to insufficient core size >* Slower speed fans causing cooling problems (if ac fans) >* Higher ripple currents in the rectification filter >capacitors may >increase causing higher internal temperatures which will lead >to lower life >* Lower dc output from capacitor input rectification filter >* Decreased low-line tolerance > >Richard Woods > > -- > From: Ravinder Ajmani [SMTP:ajm...@us.ibm.com] > Sent: Monday, May 14, 2001 11:49 AM > To: emc-p...@ieee.org > Subject: 120V appliance on 240V supply > > > > Hi, > I am interested in knowing if a 120V, 60Hz microwave oven can be >safely > used on a 240V, 50Hz mains supply with a step-down transformer. > > Regards, Ravinder > > Email: ajm...@us.ibm.com > >*** > > Always do right. This will gratify some people and astonish the >rest. > Mark Twain --- 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,"
RE: 120V appliance on 240V supply
Hi Ravinder, I have read the other replies that advise to check the voltage and frequency rating of the microwave's power supply. They also warn of the effects of changing power frequencies.All good advice. I have another concern to add. Remember the recent thread about single phase, split phase, two phase, three phase ...? Make sure that you know what "phase" or "polarity" of AC voltage your microwave was designed for. I don't want to give any more particular instructions since I don't know exactly what type of transformer you're using ... For me to recommend an actual wiring diagram without more facts would be foolish. (even by my standards, which are pretty low) All that I can say is use caution and make sure that you keep track of exactly which wires are floating and which wires are grounded. Some 120VAC devices don't care about polarity. However, some do!!! The microwave's designers may have made certain assumptions regarding the polarity of input voltage. Violating these assumptions could lead to an unsafe condition or an overstress on certain components in the microwave's power supply. I would be glad to correspond furthur (offline) about particulars. Best regards, Chris --- 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,"
RE: Resubmittals under the RTTE Directive
Depends on your route to compliance. If you used Annex IV, or you should consult your Notified Body. If harmonised standards exist for your product and you self-declared in accordance with Annex III, then I would say all you need to do is update your Regulatory Technical File to include your new test reports, if any, and the technical diagrams reflecting the design changes. ~ Sam Wismer Lead Regulatory Engineer/ Radio Approvals Engineer LXE, Inc. (770) 447-4224 Ext. 3654 Visit Our Website at: http://www.ems-t.com -Original Message- From: rehel...@mmm.com [mailto:rehel...@mmm.com] Sent: Monday, May 14, 2001 12:54 PM To: emc-p...@majordomo.ieee.org Subject: Resubmittals under the RTTE Directive Under what conditions/design changes does an intentional radiator need to be resubmitted under the RTTE Directive? In the U.S., resubmission is required for Class 2 changes (essentially anything that changes the output such as changes in power, antenna, frequency, modulation, etc.). Is there a reference document/data that applies to the RTTE Directive in this area? Bob Heller 3M Product Safety, 76-1-01 St. Paul, MN 55107-1208 Tel: 651- 778-6336 Fax: 651-778-6252 --- 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," <>
RE: Capacitor Discharge Test
Martin, An article in Compliance Engineer, Jan/Feb 2001. Might shed some light on this. See Article on page 36. Case Study: Building a Bridge Between Product Safety and EMC. Ron Duffy -Original Message- From: Allen, John [mailto:john.al...@uk.thalesgroup.com] Sent: Monday, May 14, 2001 01:32 To: 'marti...@appliedbiosystems.com'; emc-p...@majordomo.ieee.org Cc: Marcus Murphy Subject: RE: Capacitor Discharge Test Martin Having read several other contributors comments on your question, I have to say that I totally agree with them (test with the switch in both positions) for one very practical reason. I know of several occasions where personnel have lifted disconnected equipment by wrapping their arms around it - and then dropped it again by reflex when their fingers touched the pins of the plug and they got a non-fatal shock from the charged capacitors on the plug-side of the switch. In one case the person suffered a badly injured foot (20-30lbs from 4feet up make a hell of an impact on your foot), and in the other case the weight missed the person's foot - but I then spent many hours trying to defend my company which supplied the equipment (even though it complied with the standard IEC380 - it was a long time ago! - and met the same requirements as 60950 does now)! I would expect that other forum participants will be able to relate similar incidences. Personaly, based on the above experiences, I play safe and apply the test whatever capacitance is across the pins with the switch open. As I said for the second example, even capacitance at/below the compliance limit is enough to cause the reflex action which may cause the recipient of the shock to involuntaritarily do something which results in harm to himself (or someone else). Given the current effects of product liability legislation I would take any chances at all! John Allen Thales Defence Communications Division Bracknell, UK -Original Message- From: marti...@appliedbiosystems.com [mailto:marti...@appliedbiosystems.com] Sent: 11 May 2001 17:31 To: emc-p...@majordomo.ieee.org Subject: Capacitor Discharge Test We evaluate our laboratory equipment to UL 3101-1, CSA 1010.1 and EN 61010-1. Section 6.10.3 of UL 3101-1 states "If plug pins of cord-connected equipment receive a charge from an internal capacitor, the pins shall not be HAZARDOUS LIVE 5s after disconnection of the supply". We have always performed this test with the power switch in the ON position and would have the unit running then unplug the power cord and take our reading on the oscilloscope. We have never measured any voltages above the HAZARDOUS LIVE limits of 30Vrms, 42.4V peak or 60Vdc. Our new NRTL Engineer has now also requested us to perform this test with the power switch in the OFF position. With the switch in the off position our voltages after 5 seconds are close to line voltage. The NRTL is considering this a failure. However, UL 3101-1 also states in Section 6.10.3 "For plugs receiving a charge from an internal capacitor, the measurements of 6.3 are made to establish that the levels of 6.3.1.3 are not exceeded." 6.3.1.3 requires measuring the overall capacitance from the unit. Our NRTL states that there is no method available to measure the overall capacitance of the unit. Has anyone else in the group had any experience with this issue? Does your NRTL require testing with the switch in the OFF position? Do your units fail with the switch in the OFF position? Is it a failure just because the voltage limits are exceeded, or is it only a failure if the current and capacitance limits are exceeded. (Similar to the Permissible Limits Requirements). Have you had any experience with NRTL's not being able to measure the overall capacitance? All responses are greatly appreciated. Regards Joe Martin Applied Biosystems marti...@appliedbiosystems.com --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: 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 lis
Resubmittals under the RTTE Directive
Under what conditions/design changes does an intentional radiator need to be resubmitted under the RTTE Directive? In the U.S., resubmission is required for Class 2 changes (essentially anything that changes the output such as changes in power, antenna, frequency, modulation, etc.). Is there a reference document/data that applies to the RTTE Directive in this area? Bob Heller 3M Product Safety, 76-1-01 St. Paul, MN 55107-1208 Tel: 651- 778-6336 Fax: 651-778-6252 --- 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,"
RE: Voltage vs. Power
>-Original Message- >From: Doug McKean [mailto:dmck...@corp.auspex.com] >Sent: Friday, May 11, 2001 5:39 PM >To: emc-p...@ieee.org >Subject: Re: Voltage vs. Power > > > >"Ken Javor" wrote: >> >> I wasn't going to weigh in on this, but here goes. For residential >and >> commercial non-industrial use, heating and air-conditioning must >consume the >> most power. Since these are feedback controlled systems, lowering >power >> consumption by reducing line voltage would only increase the amount >of time >> the heater/ac system was "on." Am I missing something? > >I hope some people are still reading this thread. > >Interesting. I took a 120vac/60Hz fan in the lab and tested >it to see what effects I'd get lo-lining a synchronous device. >I'm using a Pacific SmartSource 360-AMX AC power >source which gives me several readouts. > >InputKVAKW PF Amps Amps > vac RMSPeak > >125 0.049 0.051 0.979 0.413 0.650 >120 0.046 0.048 0.978 0.409 0.625 >115 0.042 0.045 0.976 0.393 0.600 >110 0.039 0.041 0.976 0.381 0.625 >108 0.041 0.040 0.978 0.372 0.575 >105 0.039 0.038 0.975 0.366 0.600 >100 0.036 0.035 0.975 0.350 0.575 > >A 5% reduction from 120vac to 115vac (if you're willing to >accept 115 being approx. 114) yields the following changes ... > > KVA -8.70% > KW-6.25% > PF -0.20% > AMPS RMS -3.91% > AMPS PEAK -4.00% > >A 10% reduction from 120vac to 108vac yields the following >changes ... > > KVA -10.9% > KW-16.7% > PF 0.0% > AMPS RMS -9.0% > AMPS PEAK -8.0% > >So, the other concern I have is the regular variation of the public >mains. The grid must vary and I don't have any information how >much it varies during the course of, what, a week, month, year? >If the line was reduced to 108vac, what would be the anticipated >low line during normal operation? > >- Doug McKean > > > I too, didn't want to jump into this, but Doug's data prompts me to add one point. We use electrical energy mainly in two residential ways. First, there are "informational" (lacking any better word) uses, such as operating a television, clock or doorbell transformer. These loads may use a bit less power if the voltage is reduced. I called them "informational", since they convey information rather than perform work. The second group are "working" devices. These devices transform electrical energy into physical work. Examples of these are heating water, pumping water, compressing gas, lifting mass, blowing air and creating light. In all of these cases, we are modifying the state of matter by applying energy. As an example, if we want to move 500 gallons of water (about 3000 pounds) to a tank 100 feet above ground, we need to apply 300K foot-pounds of energy to do it (neglecting all the little losses). That 300K ft-lbs (about 0.1 kWHr) must be expended to do the job. If the voltage supply is reduced, the pump motor may draw less power, but it will then do less mechanical work in a unit of time. You still need to expend the same amount of energy; it just takes longer to complete the work. Regards, Ed Ed Price ed.pr...@cubic.com Electromagnetic Compatibility Lab Cubic Defense Systems San Diego, CA USA 858-505-2780 (Voice) 858-505-1583 (Fax) Military & Avionics EMC Services Is Our Specialty Shake-Bake-Shock - Metrology - Reliability Analysis --- 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,"
Re: 120V appliance on 240V supply
They will deliver less powerabour 50/60 of what you expect. The power supplies in those ovens are quite inexpensive and use a single rectifying diode. When the voltage gets high enough, the microwave bursts on for a short time. Thus, if operated from 50 Hz instead of 60 Hz, the power will drop proportional to the frequency. Don't know about any deleterious effects that would cause concern. - Robert - Robert A. Macy, PEm...@california.com 408 286 3985 fx 408 297 9121 AJM International Electronics Consultants 619 North First St, San Jose, CA 95112 -Original Message- From: Ravinder Ajmani To: emc-p...@ieee.org List-Post: emc-pstc@listserv.ieee.org Date: Monday, May 14, 2001 9:24 AM Subject: 120V appliance on 240V supply > > >Hi, >I am interested in knowing if a 120V, 60Hz microwave oven can be safely >used on a 240V, 50Hz mains supply with a step-down transformer. > >Regards, Ravinder > >Email: ajm...@us.ibm.com --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: 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,"
Re: 120V appliance on 240V supply
Hi Ravinder: > I am interested in knowing if a 120V, 60Hz microwave oven can be safely > used on a 240V, 50Hz mains supply with a step-down transformer. In essence, you are asking if a microwave oven rated for 60 Hz will operate safely at 50 Hz. I would guess that the microwave oven uses both a mains-frequency transformer and a mains-frequency fan. The problem is that of the quantity of iron in both the transformer and the fan. 50 Hz requires more iron to prevent saturation of the core. If there is insufficient iron, the devices will tend to overheat at maximum or even normal load. The fan will run slower. If the devices are conservatively designed, they will work okay, although without margin, at 50 Hz. Overheating of the transformer or the fan motor will initially produce an odor followed by smoke. I believe microwave ovens have an internal fuse, so this should operate before things get too hot. In addition, microwave ovens are in metal enclosures, so if a failure should occur, the fire is not likely to escape the enclosure. As a general rule, for electro-magnetic devices such as transformers and motors, you run a risk of failure when the frequency goes down. Best regards, Rich --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: 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,"
RE: 120V appliance on 240V supply
If the frequency rating of the product is 50-60 Hz, it should be OK. However, if the rating is only 60 Hz, there may be the following frequency sensitive concerns: * Lower output from transformers due to insufficient core size * Slower speed fans causing cooling problems (if ac fans) * Higher ripple currents in the rectification filter capacitors may increase causing higher internal temperatures which will lead to lower life * Lower dc output from capacitor input rectification filter * Decreased low-line tolerance Richard Woods -- From: Ravinder Ajmani [SMTP:ajm...@us.ibm.com] Sent: Monday, May 14, 2001 11:49 AM To: emc-p...@ieee.org Subject: 120V appliance on 240V supply Hi, I am interested in knowing if a 120V, 60Hz microwave oven can be safely used on a 240V, 50Hz mains supply with a step-down transformer. Regards, Ravinder Email: ajm...@us.ibm.com *** Always do right. This will gratify some people and astonish the rest. Mark Twain --- 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 searchable on the web at: http://www.rcic.com/ click on "Virtual Conference Hall,"
China
I am aware of China's requirements for safety and EMC approvals for imported equipment, but I have no clue as to the requirements for products manufactured in China. Can someone enlighten me, particularly about ITE and power supplies? Richard Woods --- 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,"
120V appliance on 240V supply
Hi, I am interested in knowing if a 120V, 60Hz microwave oven can be safely used on a 240V, 50Hz mains supply with a step-down transformer. Regards, Ravinder Email: ajm...@us.ibm.com *** Always do right. This will gratify some people and astonish the rest. . Mark Twain --- 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,"
Job Opening - Product Safety Compliance
Position Open - Product Safety Engineer Nemko Dallas, TX is looking for engineers with a background in product safety to join our team. Nemko Dallas is a subsidiary of Nemko AS, a Notified and Competent body in the European Union. In Texas, we have a full-service testing laboratory and evaluate products from third party manufacturers for the purpose of obtaining UL, CSA, BABT and Nordic marks and approvals, as well as testing for compliance to the European Union Directives and the CB scheme. Applicants should have experience with IEC, UL and CSA standards. Applicants should have excellent oral and written communication skills, testing and report writing experience, and good organizational skills. Nemko offers a competitive salary and a solid benefit package: medical, dental, 401K, etc., along with a challenging, dynamic work environment. Send your resume to (972) 436-2667, attn: Phillip Godfrey, or email to: pgodf...@icomply.com --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: 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,"
RE: Capacitor Discharge Test
Joe, On the "domestic use" front of 60950 ITE. What if a child were to unplug say; a PC or Monitor from the wall and introduce the blades of the plug into the mouth. Children put everything into their mouths. Serge Bousquet Safety Engineering Services Asia -Original Message- From: owner-emc-p...@ieee.org [mailto:owner-emc-p...@ieee.org]On Behalf Of Allen, John Sent: Monday, May 14, 2001 2:32 PM To: 'marti...@appliedbiosystems.com'; emc-p...@majordomo.ieee.org Cc: Marcus Murphy Subject: RE: Capacitor Discharge Test Martin Having read several other contributors comments on your question, I have to say that I totally agree with them (test with the switch in both positions) for one very practical reason. I know of several occasions where personnel have lifted disconnected equipment by wrapping their arms around it - and then dropped it again by reflex when their fingers touched the pins of the plug and they got a non-fatal shock from the charged capacitors on the plug-side of the switch. In one case the person suffered a badly injured foot (20-30lbs from 4feet up make a hell of an impact on your foot), and in the other case the weight missed the person's foot - but I then spent many hours trying to defend my company which supplied the equipment (even though it complied with the standard IEC380 - it was a long time ago! - and met the same requirements as 60950 does now)! I would expect that other forum participants will be able to relate similar incidences. Personaly, based on the above experiences, I play safe and apply the test whatever capacitance is across the pins with the switch open. As I said for the second example, even capacitance at/below the compliance limit is enough to cause the reflex action which may cause the recipient of the shock to involuntaritarily do something which results in harm to himself (or someone else). Given the current effects of product liability legislation I would take any chances at all! John Allen Thales Defence Communications Division Bracknell, UK -Original Message- From: marti...@appliedbiosystems.com [mailto:marti...@appliedbiosystems.com] Sent: 11 May 2001 17:31 To: emc-p...@majordomo.ieee.org Subject: Capacitor Discharge Test We evaluate our laboratory equipment to UL 3101-1, CSA 1010.1 and EN 61010-1. Section 6.10.3 of UL 3101-1 states "If plug pins of cord-connected equipment receive a charge from an internal capacitor, the pins shall not be HAZARDOUS LIVE 5s after disconnection of the supply". We have always performed this test with the power switch in the ON position and would have the unit running then unplug the power cord and take our reading on the oscilloscope. We have never measured any voltages above the HAZARDOUS LIVE limits of 30Vrms, 42.4V peak or 60Vdc. Our new NRTL Engineer has now also requested us to perform this test with the power switch in the OFF position. With the switch in the off position our voltages after 5 seconds are close to line voltage. The NRTL is considering this a failure. However, UL 3101-1 also states in Section 6.10.3 "For plugs receiving a charge from an internal capacitor, the measurements of 6.3 are made to establish that the levels of 6.3.1.3 are not exceeded." 6.3.1.3 requires measuring the overall capacitance from the unit. Our NRTL states that there is no method available to measure the overall capacitance of the unit. Has anyone else in the group had any experience with this issue? Does your NRTL require testing with the switch in the OFF position? Do your units fail with the switch in the OFF position? Is it a failure just because the voltage limits are exceeded, or is it only a failure if the current and capacitance limits are exceeded. (Similar to the Permissible Limits Requirements). Have you had any experience with NRTL's not being able to measure the overall capacitance? All responses are greatly appreciated. Regards Joe Martin Applied Biosystems marti...@appliedbiosystems.com --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: 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:
RE: Capacitor Discharge Test
Martin Having read several other contributors comments on your question, I have to say that I totally agree with them (test with the switch in both positions) for one very practical reason. I know of several occasions where personnel have lifted disconnected equipment by wrapping their arms around it - and then dropped it again by reflex when their fingers touched the pins of the plug and they got a non-fatal shock from the charged capacitors on the plug-side of the switch. In one case the person suffered a badly injured foot (20-30lbs from 4feet up make a hell of an impact on your foot), and in the other case the weight missed the person's foot - but I then spent many hours trying to defend my company which supplied the equipment (even though it complied with the standard IEC380 - it was a long time ago! - and met the same requirements as 60950 does now)! I would expect that other forum participants will be able to relate similar incidences. Personaly, based on the above experiences, I play safe and apply the test whatever capacitance is across the pins with the switch open. As I said for the second example, even capacitance at/below the compliance limit is enough to cause the reflex action which may cause the recipient of the shock to involuntaritarily do something which results in harm to himself (or someone else). Given the current effects of product liability legislation I would take any chances at all! John Allen Thales Defence Communications Division Bracknell, UK -Original Message- From: marti...@appliedbiosystems.com [mailto:marti...@appliedbiosystems.com] Sent: 11 May 2001 17:31 To: emc-p...@majordomo.ieee.org Subject: Capacitor Discharge Test We evaluate our laboratory equipment to UL 3101-1, CSA 1010.1 and EN 61010-1. Section 6.10.3 of UL 3101-1 states "If plug pins of cord-connected equipment receive a charge from an internal capacitor, the pins shall not be HAZARDOUS LIVE 5s after disconnection of the supply". We have always performed this test with the power switch in the ON position and would have the unit running then unplug the power cord and take our reading on the oscilloscope. We have never measured any voltages above the HAZARDOUS LIVE limits of 30Vrms, 42.4V peak or 60Vdc. Our new NRTL Engineer has now also requested us to perform this test with the power switch in the OFF position. With the switch in the off position our voltages after 5 seconds are close to line voltage. The NRTL is considering this a failure. However, UL 3101-1 also states in Section 6.10.3 "For plugs receiving a charge from an internal capacitor, the measurements of 6.3 are made to establish that the levels of 6.3.1.3 are not exceeded." 6.3.1.3 requires measuring the overall capacitance from the unit. Our NRTL states that there is no method available to measure the overall capacitance of the unit. Has anyone else in the group had any experience with this issue? Does your NRTL require testing with the switch in the OFF position? Do your units fail with the switch in the OFF position? Is it a failure just because the voltage limits are exceeded, or is it only a failure if the current and capacitance limits are exceeded. (Similar to the Permissible Limits Requirements). Have you had any experience with NRTL's not being able to measure the overall capacitance? All responses are greatly appreciated. Regards Joe Martin Applied Biosystems marti...@appliedbiosystems.com --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: 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 searchable on the web at: http://www.rcic.com/ click on "Virtual Conference Hall,"
Re: LVD directive in Scandinavia
Dear Patrick, Thanks for your response. According to your explanation, no matter compliant EN 60065 or IEC 60065 standard just cover the neutral part of required standard and all require additional country deviation tests. Do the Scandinavian countries traditionally accept VDE standard? If so, would it be easier to build the product to a single standard rather than multiple standards. The testing would be simpler as well. Is it a real case in the world? Thanks and regards, Raymond Li Omni Source Asia Ltd. "Patrick Wong" , 12/05/01 09:20cc: a Subject: Re: LVD directive in Scandinavia Dear Raymond, As EU countries will employ Euro-Norm standards for LVD testing, the Scandinavia as well as other EU's uses EN with national deviations for testing. This apply to the Scandinavia FIMKO, SEMKO, NEMKO as well as DEMKO. Other national standards such as DIN and BSEN are all based on EN and converted into their national languages. Regards Patrick Wong Senior Manger, Electrical and EMC Dept. The Hong Kong Standards and Testing Centre - Original Message - From: To: Sent: Friday, May 11, 2001 3:08 PM Subject: LVD directive in Scandinavia > > Understand Scandinavia is part of EU or EFTA and LVD has to be applied to > electronics and electrical products. Scandinavia includes a number of > countries. Do they commonly accept one standard, I learnt German standard, > or different country standards? > > We have following ideas to approve the products to LVD and would like to > have some input from experienced personnel. > > Take audio & video products as an example:- > > 1. On top of compliant report of BS EN60065, get the additional test > according to countries deviations. > > 2. Get compliant report of EN60065 only. > > 3. Get CB IEC 60065 report only. > > Thanks and regards, > > Raymond Li > Omni Source Asia Ltd. > > > ** > Legally privileged/Confidential Information may be contained in this > message. If you are not the addressee(s) legally indicated in this message > (or responsible for delivery of the message to such person), you may not > copy or deliver this message to anyone. In such case, you should destroy > this message, and notify us immediately. If you or your employer does not > consent to Internet e-mail messages of this kind, please advise us > immediately. Opinions, conclusions and other information expressed in this > message are not given or endorsed by my firm or employer unless otherwise > indicated by an authorised representative independent of this message. > Please note that neither my employer nor I accept any responsibility for > viruses and it is your responsibility to scan attachments (if any). > > > --- > 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 searchable on the web at: http://www.rcic.com/ click on "Virtual Conference Hall,"
