Re: Secondary Grounding
Hi Chris, As usual, Rich is correct that removing more then one ground connection would be an improper single fault test. However, Rich's comment... >A single-fault test is with one ground open (a meaningless >test when there is a second ground in place)... Is not quite accurate, the test is only meaningless if you have already verified that both grounds are fully contiguous throughout the equipment. I have once or twice ran across multiple ground connections in larger IT equipment where one of the grounds did not have continuity throughout the equipment. In that case, removing the good ground does expose you to a higher leakage current, as the second ground is poorly constructed and not functioning. For that reason, it is crucial that your verify ground performance for each ground, throughout the equipment, prior to single fault testing. Best Regards, Frank W. ---[From the computer of...]- Mr. Frank West Sr. Engineer TUV Rheinland 7853 SW Cirrus Dr. Beaverton, OR. 97008 T 503-469-8880 Ext 205 F 503-469-8881 fw...@us.tuv.com Rich Nute To: chris.maxw...@nettest.com Sent by: cc: emc-p...@majordomo.ieee.org owner-emc-pstc@majordomSubject: Re: Secondary Grounding o.ieee.org 06/01/2001 01:55 PM Please respond to Rich Nute Hi Chris: Consider a product with two, independent protective grounding/earthing connections. This may be by means of two power cords (as is done for uptime reliablity by employing parallel power supplies) or by means of one power cord and a separate ground connection (as, for example, by mounting in a grounded rack). > Safety standards call for single fault testing. For Class I equipment, one > of the single fault test conditions is removal of the ground connection. Agreed. The disconnection of one ground is a single- fault condition. > I'm curious how most test labs would reconcile the two statements above. My > guess is that they would interpret removal of ground to mean removal of all > ground connections. So putting on an extra ground wire wouldn't help. It > would just make the safety engineer disconnect another wire to perform the > test. I don't agree. The requirement is that of a single- fault condition. If normal operation employs redundant grounding, then a single-fault condition is that of failure of one ground connection. > "What if the product is used in a building or environment with an unreliable > ground?" or "How can you garantee that the product's ground potential will > always be equal to the potential of the floor where the user is standing" If the ground within the building installation is subject to failure, then the fault is that of the building installation, not of the product. So, it would be nonsense to require a product single-fault "no-ground" test on that basis. A faulty ground in the building installation allows cumulation of leakage currents from all equipment to be available on each and every grounded equipment, a truly dangerous situation because the cumulative leakage current could be in the hundreds of milliamperes! (Ironically, the equipment with a faulty ground would be the only safe equipment in such a situation!) I was recently invited to comment on the subject of single-fault testing requirements for products with multiple power cords. My argument was based on the idea that any product with multiple power cords is "professional" equipment where the advantage of such equipment is only achieved by connecting to multiple power sources. So, this
RE: Secondary Grounding
A solution for rack mounted ITE equipment is to have an earth ground terminal on the AC inlet or DC power terminal block that is connected to the chassis. As a second grounding means, the chassis can be provided with two threaded holes for the connection of a Listed grounding lug for bonding the equipment to the metal mounting rack of other suitable grounding point. This ensures that the equipment can reliably grounded, even if the grounding conductor from the supply source is unreliable. The Listed grounding lug would need to be supplied with the equipment. Richard Meyette Terawave Communications 30680 Huntwood Avenue Hayward, CA 94544 Phone: 510-401-6622 Fax: 510-401-6628 Email: rmeye...@terawave.com -Original Message- From: Chris Maxwell [mailto:chris.maxw...@nettest.com] Sent: Friday, June 01, 2001 12:12 PM To: emc-p...@majordomo.ieee.org Subject: RE: Secondary Grounding Hmm, This question centers around whether two separate ground cables equals double protection. Safety standards call for single fault testing. For Class I equipment, one of the single fault test conditions is removal of the ground connection. I'm curious how most test labs would reconcile the two statements above. My guess is that they would interpret removal of ground to mean removal of all ground connections. So putting on an extra ground wire wouldn't help. It would just make the safety engineer disconnect another wire to perform the test. Seems to me that there would be no way to talk them in to this one. No matter how many ground wires you put on, or how well you secure them, they could always say, "What if the product is used in a building or environment with an unreliable ground?" or "How can you garantee that the product's ground potential will always be equal to the potential of the floor where the user is standing" I don't have a comeback for that. If anyone does have a comeback; I'd nominate them for the "Safety Compliance Engineer Hall of Fame" ;-) (I'd also want them to be my lawyer.) !PLEASE NOTE THE NEW EMAIL ADDRESS Chris Maxwell Design Engineer NetTest 6 Rhoads Drive, Building 4 Utica,NY 13502 email: chris.maxw...@nettest.com phone: 315-266-5128 fax: 315-797-8024 --- 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: Secondary Grounding
Hi Chris: Consider a product with two, independent protective grounding/earthing connections. This may be by means of two power cords (as is done for uptime reliablity by employing parallel power supplies) or by means of one power cord and a separate ground connection (as, for example, by mounting in a grounded rack). > Safety standards call for single fault testing. For Class I equipment, one > of the single fault test conditions is removal of the ground connection. Agreed. The disconnection of one ground is a single- fault condition. > I'm curious how most test labs would reconcile the two statements above. My > guess is that they would interpret removal of ground to mean removal of all > ground connections. So putting on an extra ground wire wouldn't help. It > would just make the safety engineer disconnect another wire to perform the > test. I don't agree. The requirement is that of a single- fault condition. If normal operation employs redundant grounding, then a single-fault condition is that of failure of one ground connection. > "What if the product is used in a building or environment with an unreliable > ground?" or "How can you garantee that the product's ground potential will > always be equal to the potential of the floor where the user is standing" If the ground within the building installation is subject to failure, then the fault is that of the building installation, not of the product. So, it would be nonsense to require a product single-fault "no-ground" test on that basis. A faulty ground in the building installation allows cumulation of leakage currents from all equipment to be available on each and every grounded equipment, a truly dangerous situation because the cumulative leakage current could be in the hundreds of milliamperes! (Ironically, the equipment with a faulty ground would be the only safe equipment in such a situation!) I was recently invited to comment on the subject of single-fault testing requirements for products with multiple power cords. My argument was based on the idea that any product with multiple power cords is "professional" equipment where the advantage of such equipment is only achieved by connecting to multiple power sources. So, this is normal operation. A single-fault test is with one ground open (a meaningless test when there is a second ground in place). I recommended a leakage current test with one power cord connected which would simulate the situation where the redundancy was not used, and there was a fault in the grounding system. 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,"
spacings for En 50021
We use En 50021 for our Class 1 Zone 2 compliance. In the preliminary version, the creepage and clearences were equal to the UL standards UL 840 and UL 508. When the EN version was adopted, the creepage and clearences for pollution degree 2 were eliminated, what luck thats the spacings that we use. Does any one have any idea why the distances for pollution degree 2 were eliminated. I asked UL and they do not seem to know. Thanks Jim Sotherden Agency Coordinator/Test Engineer Technology Compliance Team GE Fanuc 804-978-.6224 804-978-5588 fax --- 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,"
X ray safety interlocks.
All, Paragraph C4 in cfr 1020.40 States: " Each door of a cabinet X-Ray system shall have a minimum of two safety interlocks. One, but not both of the required interlocks shall be such that the door opening results in physical disconnection of the energy supply circuit to the high voltage generator, and such disconection shall not be dependent upon any moving part other than the door". I see this as an end result and not stating explicitly the "how" to accomplish the end results. If that is correct, can a low voltage relay be used to control another relay which has a set of contacts that when activated, removes the energy supply circuit to the high volatage generator? This combination would make up "one" of the two safety interlocks required. This may seem a round about way to have two interlock circuits but its the design that was inherited when my Company purchased the product line from another manufacturer. Currently Im in the process of filling out the initial report for the FDA and Im curious if this design is acceptable and not require a change to meet the intent of paragraph C4. Bob Chaplis Genrad. --- 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: Secondary Grounding
Hmm, This question centers around whether two separate ground cables equals double protection. Safety standards call for single fault testing. For Class I equipment, one of the single fault test conditions is removal of the ground connection. I'm curious how most test labs would reconcile the two statements above. My guess is that they would interpret removal of ground to mean removal of all ground connections. So putting on an extra ground wire wouldn't help. It would just make the safety engineer disconnect another wire to perform the test. Seems to me that there would be no way to talk them in to this one. No matter how many ground wires you put on, or how well you secure them, they could always say, "What if the product is used in a building or environment with an unreliable ground?" or "How can you garantee that the product's ground potential will always be equal to the potential of the floor where the user is standing" I don't have a comeback for that. If anyone does have a comeback; I'd nominate them for the "Safety Compliance Engineer Hall of Fame" ;-) (I'd also want them to be my lawyer.) !PLEASE NOTE THE NEW EMAIL ADDRESS Chris Maxwell Design Engineer NetTest 6 Rhoads Drive, Building 4 Utica,NY 13502 email: chris.maxw...@nettest.com phone: 315-266-5128 fax: 315-797-8024 --- 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: UL Mark
Properly the UL mark should go on last because it doesn't comply until all the processes are complete. However You can apply the mark before hipot but a hipot failure should never occur. A unit that does not pass should be sent back through the process until it passes however many times it takes. You should have a method to control this to make sure a failing unit never ships. Some products have the mark stamped in the metal enclosure before the unit is even assembled so when you put it on is not the issue. The issue is that you never ship a non compliant unit with the UL mark on it. Your MFG or ISO9000 procedures should reflect and control this. Monty Griffith Test Engineer Intergraph Government Solutions Federal Hardware Engineering Dept. 170 Graphics Drive Madison, AL 35758 Ph: 256 730-4265 FX: 256 730-6816 Email: mjgri...@ingr.com -Original Message- From: Dave Wilson [mailto:dwil...@alidian.com] Sent: Friday, June 01, 2001 11:12 AM To: 'emc-p...@ieee.org' Subject:UL Mark Can anybody tell me where it is defined at what point in production it is permissible to apply the UL mark? Can it only be done after the hi-pot has passed? Or is it OK to have the label applied before the test as long as the units are clearly marked as having failed hi-pot? Thanks in advance, Dave Wilson Alidian Networks Inc. --- 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: UL Mark
Hi Dave: > Can anybody tell me where it is defined at what point in production it is > permissible to apply the UL mark? Can it only be done after the hi-pot has > passed? Or is it OK to have the label applied before the test as long as the > units are clearly marked as having failed hi-pot? You should direct this question to UL. :-) This is one of those questions that if you should ask UL, you must be prepared to live with the worst-case answer. This is a question that is better not asked because... Strictly speaking, the UL mark goes on *AFTER* the product meets all the UL requirements, including passing the hi-pot test. I believe this is specified in the front matter of your UL FUS Procedure. But, putting the UL mark on AFTER these processes implies a stick-on label and a specific production step. These two implications may not be compatible with your production sequences. And, such implications would prohibit molding the mark into a plastic part (which many of us do). In real life, the mark can go on at any step in the production process. In practice, UL looks the other way in terms of the sequence step in which the mark is applied. If UL had any doubts about your product and the quality of your production, UL would probably insist that the mark be applied AFTER the hi-pot test. 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,"
[Fwd: RE: ESD Question]
Forwarded for Mike Hopkins. Original Message Subject: RE: ESD Question List-Post: emc-pstc@listserv.ieee.org Date: Wed, 30 May 2001 16:06:48 -0400 From: Mike Hopkins To: "'Chris Maxwell'" ,"'Sandy Mazzola'", emc-p...@majordomo.ieee.org There is an amendment to IEC 61000-4-2 in process that is intended to clarify the issue of connector pins. I basically states that for connectors with metal shells, a contact mode discharge is performed to the shell. For plastic connectors, an air discharge is done in the vicinity of the connector -- if a break-down to a pin occurs in either case, tough luck. There was never any intention that discharges be done to individual pins in a connector. Some other specific exclusions include ESD sensitive connectors -- scope inputs, etc... that are marked as ESD sensitive and there is reference to that in the product documentation. Also excluded are battery contacts which might be contacted when the batteries are changed but are not accessed during operation of the product. Hope this is helpful.. Best Regards, Mike Hopkins KeyTek (member IEC SC77B WG9, which is the working group responsible for IEC 61000-4-2) -Original Message- From: Chris Maxwell [mailto:chris.maxw...@nettest.com] Sent: Wednesday, May 30, 2001 2:07 PM To: 'Sandy Mazzola'; emc-p...@majordomo.ieee.org Subject: RE: ESD Question Hi Sandy, Have you seen the sunshine in your end of New York? If you have, send it back!! Personally, I have never seen a product that required air or contact ESD testing on the individual pins of connectors. I can only speak for products tested to EN 50082-1(Generic Immunity), EN 50082-1(Generic Immunity/Heavy Industrial), ETS 300-386-1(Telcom EMC) and EN 61326-1 (Test , Measurement and Control Equipment EMC). The basic standard which covers ESD testing itself (for the product and product family standards mentioned above) is EN 61000-4-2. EN 61000-4-2 is also the basic standard which EN 55024 references for ESD testing. EN 61000-4-2 gives no definite example or statement regarding discharge to individual connector pins. It just says to discharge to all locations normally accessible by the customer (paraphrased). So, this can be rationalized either way.Apparantly, the authors of EN 55024 have already done the rationalization for you. What I have typically seen and performed is ESD testing whereby direct contact discharges are made to the shells of connectors (i.e. D-subs ) but not to the individual pins. Since EN 61000-4-2 gives no exact direction, I think that there has been a "general consensus of interpretation" (my own words) that ESD is not required on individual pins. I have heard some myth/horror stories that say otherwise from people selling ESD hardened connectors, IC's but they turned out to be exaggerations. Having said that, I must add the caveat that there may be standards and products that are an exception, especially in the military, aerospace or medical fields. I just haven't seen any. !PLEASE NOTE THE NEW EMAIL ADDRESS Chris Maxwell Design Engineer NetTest 6 Rhoads Drive, Building 4 Utica,NY 13502 email: chris.maxw...@nettest.com phone: 315-266-5128 fax: 315-797-8024 > -Original Message- > From: Sandy Mazzola [SMTP:mazzo...@symbol.com] > Sent: Wednesday, May 30, 2001 9:30 AM > To: emc-p...@majordomo.ieee.org > Subject: ESD Question > > Hi all, > >In EN 55024: 1998 Page 9 Paragraph 4.2.1, I found the following > statement: "The application of electrostatic discharges to the contacts > of open connectors is not required by this publication" > > My question is twofold has everybody interpreted this to mean that > no air discharges or contact discharges are required to the connector or > pins of the open connector. > And secondly if the answer to the above is no discharges of any type are > required, what other publications would require either air or contact > discharges to open connectors. > > Thanks > > Sandy Mazzola > > Santo Mazzola > Regulatory Engineer > Symbol Technologies Inc > 1 Symbol Plaza > Holtsville, N. Y. 11742-1300 > Phone: (631) 738-5373 > Fax: (631) 738-3318 > E-mail: mazzo...@symbol.com > > << File: Sandy Mazzola.vcf >> --- 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/
UL Mark
Can anybody tell me where it is defined at what point in production it is permissible to apply the UL mark? Can it only be done after the hi-pot has passed? Or is it OK to have the label applied before the test as long as the units are clearly marked as having failed hi-pot? Thanks in advance, Dave Wilson Alidian Networks Inc. --- 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: Surge Test Question
I've also seen this effect when testing component power supplies (off-line switch-mode converters, 50-500W). The problem became apparent when a customer added another EMI filter ahead of our power supply, creating a system we didn't anticipate. The power supply alone passed the test, but the additional EMI filter and power supply would not pass the common-mode surge test. When I sketched the AC input circuit of the composite system, I realized the surge generator was simply pulsing into several common-mode inductors and primary-ground capacitors - the circuit had no load! I set the surge generator to a relatively low voltage (200V), and connected an oscilloscope probe from the power supply AC input terminal to chassis. I saw the 200V surge ring to almost 400V! If this had been a 2kV common-mode surge, I expect that the power supply would see about 4kV primary-ground, which it was clearly not designed for. I think performing this simple test would be your best indication of surge voltages seen in your system. Since it involves primary-connected components, be sure to observe proper safety precautions. brian_ku...@leco.com wrote: >When troubleshooting surge problems on products we often see the surge pulse >to >be much higher after the line filter (testing the AC Mains with Line-Earth >surge >pulses according to EN61000-4-5). > >Can someone explain the science behind this and what effect the load might >have? >Can this increase in the surge potential be anticipated ahead of time so proper >clearances can be designed in? --- 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: EMC/RFI Gaskets
I would have to state that the polymeric material would be listed under the manufacture of that material (not necessarily the EMI gasket manufacturer) and the shield effectiveness data would be from the manufacturer of the EMI gasket. You should be able to contact the EMI gasket manufacture for this information. This is what I have experienced in the past. Good Luck! -Original Message- From: Peter Merguerian [mailto:pmerguer...@itl.co.il] Sent: Friday, June 01, 2001 8:03 AM To: "EMC-PSTC (E-mail)" < Subject: EMC/RFI Gaskets Importance: High Dear All, While UL does its' own research, under what UL category one can find polymeric insulated RFI/EMI gaskets that have been previously evaluated for flammability and shielding effectiveness? PETER S. MERGUERIAN Technical Director I.T.L. (Product Testing) Ltd. 26 Hacharoshet St., POB 211 Or Yehuda 60251, Israel Tel: + 972-(0)3-5339022 Fax: + 972-(0)3-5339019 Mobile: + 972-(0)54-838175 --- 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: EMC/RFI Gaskets
Hi Peter, Gaket material are covered as Recognized Plastics material. They are in the "yellow books", just like regular plastics material (QMFZ2). Some gasket material were Recognized under that QMFZ2 category, but there is also a special category (Q) that covers gaskets in particular. I cannot remember what that category code is, but the temp and flammability rating are similar to QMFZ2, either solid plastics or foam plastics (i.e. UL 94). I hope this helps. If you still have troubles searching them down, send me an email, and I'll shake out some cobwebs and help you out... BR, Bob Tims Engineering Project Leader Ericsson Internet Applications Inc. Woodbury, NY 11797 robert.t...@ericsson.com -Original Message- From: Peter Merguerian [mailto:pmerguer...@itl.co.il] Sent: Friday, June 01, 2001 9:03 AM To: "EMC-PSTC (E-mail)" < Subject: EMC/RFI Gaskets Importance: High Dear All, While UL does its' own research, under what UL category one can find polymeric insulated RFI/EMI gaskets that have been previously evaluated for flammability and shielding effectiveness? PETER S. MERGUERIAN Technical Director I.T.L. (Product Testing) Ltd. 26 Hacharoshet St., POB 211 Or Yehuda 60251, Israel Tel: + 972-(0)3-5339022 Fax: + 972-(0)3-5339019 Mobile: + 972-(0)54-838175 --- 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,"
EMC/RFI Gaskets
Dear All, While UL does its' own research, under what UL category one can find polymeric insulated RFI/EMI gaskets that have been previously evaluated for flammability and shielding effectiveness? PETER S. MERGUERIAN Technical Director I.T.L. (Product Testing) Ltd. 26 Hacharoshet St., POB 211 Or Yehuda 60251, Israel Tel: + 972-(0)3-5339022 Fax: + 972-(0)3-5339019 Mobile: + 972-(0)54-838175 --- 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,"
[Fwd: JISC to U.S. Code equivalency]
Forwarded for Leslie Wood. Please CC Leslie (lesliew...@aol.com) on replies. Dave Heald Original Message Subject: JISC to U.S. Code equivalency List-Post: emc-pstc@listserv.ieee.org Date: Thu, 31 May 2001 20:49:00 EDT From: lesliew...@aol.com To: emc-p...@majordomo.ieee.org Hi! Is there a good resource for determining the equivalency between JISC & US Electrical Code? Thanks, Leslie Wood --- 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,"
