RE: NEAR/ FAR FIELD CORRELATION ISSUES
I beg to differ. It is ludicrous to believe that components or for that matter subassemblies can be certified and then combined to make a compliant system. CE + CE doesn't always equal CE The reduction of emissions is highly reliant on component placement. The same parts can be arranged on circuit boards in compliant and non-compliant patterns. Same with subassemblies. While the current measurement techniques are difficult they are about as close to the truth as we can get. Even if that means an 8 dB swing from site to site. The reason that we see PCs consistently fail by as much as 20 dB is because of a lack of enforcement. Many computer manufacturers sneak through the requirements with their one of a kind golden units never to worry about compliance again. Very few get caught and it is worth the bucks to keep the production lines going rather than shutdown the lines. Who was the last computer manufacturer you heard of that was forced to shutdown until an EMC problem was fixed? I have a book of test reports on competitor's products. They fall into the categories of compliant, near compliant (looks like they tried), and fails miserably (didn't try, didn't care, and outright lied on any self declarations). The failing companies seem to be doing just as brisk a business as the passing companies without having to worry about the cost of EMC. Earl Morse Portable Division EMC Design Compaq Computer Corporation Phone: 281.927.3607 Pager: 713.717.0824 Fax: 281.927.3654 Email: earl.mo...@compaq.com mailto:earl.mo...@compaq.com -Original Message- From: Grasso, Charles (Chaz) [mailto:gra...@louisville.stortek.com] Sent: Friday, June 18, 1999 10:33 AM To: 'Lou Gnecco'; emc-p...@majordomo.ieee.org Subject:RE: NEAR/ FAR FIELD CORRELATION ISSUES I cannot agree more!! We, not the government, need to drive the technology for EMC. I have followed this thread with interest. I have long believed that if EMC was to maintain credibility we (EMC ) would have to come up with a method of demonstrating compliance in spite of the many and varied combinations. One way is to test at the component level - like our Safety brethren - and call the assembly of tested components good!! This is methodology can be made consistent with good engineering design practice unlike the existing FCC rules for Class B equipment. On the surface the FCC Rules appear to be similar to component level testing - but under the hood, they are completely different. There are PCs out there that fail by as much as 20dB. I am all for a more logical and consistent design approach to EMC!! Thank you Charles Grasso Advisory Engineer StorageTek 2270Sth 88th Street Louisville CO 80027 M/S 4247. Tel:303-673-2908 Fax:303-661-7115 email:gra...@louisville.stortek.com Web Site: http://www.ewh.ieee.org/r5/denver/rockymountainemc/ -Original Message- From: Lou Gnecco [mailto:l...@tempest-inc.com] Sent: Friday, June 18, 1999 6:52 AM To: emc-p...@majordomo.ieee.org Subject: Re: NEAR/ FAR FIELD CORRELATION ISSUES For this to work, the government would have to change the rules completely, setting a new set of near field procedures and limits. This is doable but hard to sell. A good way to start would be if we did it. If someone in industry writes up a procedure and a set of limits, then everyone could use that as a straw man, (criticizing and refining it) until eventually most people agreed. Eventually it could become an industrial (such as IEEE) standard. Then the govt would find it much easier to adopt it as is or after making their own modifications. lou - 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
Re: NEAR/ FAR FIELD CORRELATION ISSUES
Arun: I agree that a lower cost and simpler method would be nice but you have a very difficult problem to solve. Your basic problem is correlating to an OATS site. Theoretically this is possible using the equivalence principle but it is hard to do. First one must create a surface that totally incloses the system to be tested. Next you need to measure instantaneous electric and magnetic fields as a function of time and direction while the product performs all its functions over this surface. From this information, one can predict the fields at 3m or 10m. If you just find the magnitude of the magnetic field, you do not know if it will add or cancel with another magnetic field from some other place in the product. Phase and time are both important. What if I have two pulsing fields that happen a different times. Do you add them? We use near field probing to locate radiated problems and many times we will eliminate a strong near field source to find out that the far field has not changed. If you keep reducing the near field sources then eventually you find the one that solves the problem in the far field and all other fixes can then be removed. This is a good debate and I wish you luck! Sincerly, Keith Hardin Ph.D., NCE Senior Engineer Lexmark International Inc. lou%tempest-inc@interlock.lexmark.com on 06/17/99 08:24:26 AM Please respond to lou%tempest-inc@interlock.lexmark.com To: emc-pstc%majordomo.ieee@interlock.lexmark.com cc:(bcc: Keith Hardin/Lex/Lexmark) Subject: Re: NEAR/ FAR FIELD CORRELATION ISSUES Arun: I heartily agree with everything you said. Well done! It will not be easy to sell this idea to the emc world. When the standards are vague, acane and constantly-changing, and when it is unnecessarily expensive to set up and perform a test, this constitutes what is known in business as a Barrier To Entry that is, a way to artificially limit competition. Test laboratories (like us, for example) can charge more money when there are barriers to entry. People who make special instruments and antennas for EMC testing (like us) would lose out if there were fewer barriers to entry. Also people who install test shielded rooms, etc. There are substantial entrenched interests whose rice bowls would be threatened if emc became something anyone could do. I personally believe that the process can and should be simplified. It would help the manufacturers, who are the ones that really drive the economy. It would specially help small manufacturers. Like us. Lou At 11:18 AM 6/17/99 +1000, you wrote: Greetings and Salutations! I was wondering if this could be mailed out via the epc-pstc channels. I want to know if anyone is doing any work in near/ far field correlation to commercial EMC standard limits area and possibly correspond with them with a view to exchanging notes. Brief Follows: Brief: Application of Near Field and possibly Surface probe techniques in Evaluating Emissions from source equipment and correlating/quantifying this data to an OATS, LISN, Absorbing Clamp etc based measurement.. Details: We assume that the current EMC compliance regime around the world has quantified limits of compliance to which if every source equipment adheres to, then it has a reasonable chance of performing as intended in a real life situation, noting that the immunity threshold test levels are much more stringent than EM emission limits. Current EMC measurements are very cumbersome, require large expense in setting up and maintaining (calibrating) OATS, LISNS, Absorbing Clamps, Ferrite tiled lined semi- anechoics etc. Despite this expense, the measurement uncertainities are still of the order of 6 to 10dB (inherent). Every newly released EMC standard by IEC CISPR or CENELEC has potentially new transducers and new headaches from point of view of sourcing and maintenance, calibration. EMC today is where Safety was 10 years ago. I am of the opinion that EMC testing should be simplified and reasonably accessible to all end users. Continued progress and urban development has led to increasing levels of broad and narrowband noise to the extent that ambient profiles sometimes swamp out the limits; this has led to most test houses in the EU to opt for GTEMS or semi-anechoics (referred to as alternative all weather test sites) at considerable expense. Current techniques such as emission E Field prescanning in shielded rooms prior to OATS based testing with biconilog antennae have the drawbacks of peaking the emissions and reflections/standing waves. Hence: I propose to develop near or surface probe H (inverse of E) field techniques which actually senses the emission profiles and correlate them to an Absorber clamp, or OATS or LISN (Common mode fix) or whatever. Cables, panels, slots etc could be sniffed with a Loop and if it is possible to correlate this near or induction field data to compliance limits then it becomes very easy
EU participating countries
Does anyone have an updated list of the EU countries? Or better yet the countries which recoginze the EEC Directives (CE Marking). I think there are some EFTA countries included in this list. - 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).
Pacemakers
How do I know if a product MIGHT interfere with a Pacemaker or not? What types of emissions and levels are Pacemakers sensitive to? Does a product evaluation check list exist to help determine this. I know nothing about Pacemakers. BTW, we manufacture laboratory and IT equipment. Thank you, Brian
RE: NEAR/ FAR FIELD CORRELATION ISSUES
I also have been following this thread with interest, but even more practical and technically less challenging alternate methods of testing take too long for acceptance in my opinion. Forget near-field measurements with probes, I'd like to see quicker movement on acceptance of standards like EN50147-3 for fully anechoic compact chambers. I'm not going to get greedy and look for (or expect) near field or cable clamp measurement acceptance in the near future. Since I mentioned it, does anyone know if there is movement or progress in the area of standards tailored specifically for compact chambers like EN50147-3? -- Dan Roman, Compliance Engineer * mailto:dan.ro...@dialogic.com *Voice: +1 (973) 993-3000 ext. 6485 Fax: +1 (973) 993-8466 - 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).
US/CE Compatible Equipment Designs
Hello Group: My company produces a broad line of power-operated, commercial food equipment. This equipment is UL Listed for the U.S. market and a number of these models have the CE Mark for Europe. Currently, there is some overlap in design but still a number of differences mainly to satisfy requirements for the CE Mark as those standards seem to be more stringent and all-encompassing (including more stringent safety and hygiene requirements). We are investigating the possibilities of having essentially one design meet both sets of requirements or at least as close as practical what with the different voltage and frequency requirements involved, etc. I'm sure that this isn't the first time that this has been thought of or tried but I would like any comments anyone in the group might care to share as to the success (or pitfalls experienced) that they have had in attempting such. Thanks for your responses. Richard Pittenger PMI Food Equipment Group Troy, Ohio - 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: Medical Device Directive, IEC 601-1-2, and IEC 1000-3-2
On Fri, 18 Jun 1999 14:25:09 -0400, David George george.da...@unisys.comwrote: 61000-3-2 is a horizontal standard and it applies to all products unless specifically excluded by 61000-3-2. The criteria is defined by CENELEC and it is not necessarily specified by the individual product standards. This is why it is so important to watch basic and horizontal standards even though they may not called out in the product standards. These cross-the-board standards are sleepers and can effect manufacturer's through the back door. I just sent a reply on this very issue - you must have been reading my mind. Can you give examples of other horizontal standards? What search keyword would be appropriate at the CENELEC/DGIII web sites? Industry has decided to fight 61000-3-2 in the IEC and try to achieve realistic requirements. The US national committee has just released a position paper on harmonics requirements. If anyone needs a copy I can post it on this net. Yes, I'd like to see it. Dave George Unisys -Original Message- From: plaw...@west.net [mailto:plaw...@west.net] Sent: Thursday, June 17, 1999 7:55 PM To: emc-p...@majordomo.ieee.org Subject: Medical Device Directive, IEC 601-1-2, and IEC 1000-3-2 I was asked the following question, and wasn't sure about the answer: 1) A manufacturer can claim his system complies with the Medical Device Directive by testing to EN 60601-1-2:1993. 2) EN 60601-1-2:1993 does not have any requirements to test to IEC 1000-3-2. 3) Does that mean that the harmonic standard does not apply to this system when it becomes mandatory in 2001? I realize the Second Edition of IEC60601-1-2 is just around the corner, and that edition _does_ call out the harmonic test. However, I've been told that it may not take effect until 2003. -- Patrick Lawler plaw...@west.net - 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: Medical Device Directive, IEC 601-1-2, and IEC 1000-3-2
Yes but does it appear in the Official Journal for the Medical Device Directive? I don't believe it does but I am not sure. If not then it is not applicable. Dave Clark -Original Message- From: rehel...@mmm.com [mailto:rehel...@mmm.com] Sent: Friday, June 18, 1999 8:48 AM To: plaw...@west.net Cc: emc-p...@majordomo.ieee.org Subject: Re: Medical Device Directive, IEC 601-1-2, and IEC 1000-3-2 It is my understanding that 61000-3-2 is a family standard (at least that is what it says in the introduction of the copy that I have) and as such includes all equipment equal to or less than 16 amps. Bob Heller === === plaw...@west.net (Patrick Lawler) on 06/17/99 06:55:21 PM Please respond to plaw...@west.net (Patrick Lawler) To: emc-p...@majordomo.ieee.org cc:(bcc: Robert E. Heller/US-Corporate/3M/US) Subject: Medical Device Directive, IEC 601-1-2, and IEC 1000-3-2 I was asked the following question, and wasn't sure about the answer: 1) A manufacturer can claim his system complies with the Medical Device Directive by testing to EN 60601-1-2:1993. 2) EN 60601-1-2:1993 does not have any requirements to test to IEC 1000-3-2. 3) Does that mean that the harmonic standard does not apply to this system when it becomes mandatory in 2001? I realize the Second Edition of IEC60601-1-2 is just around the corner, and that edition _does_ call out the harmonic test. However, I've been told that it may not take effect until 2003. -- Patrick Lawler plaw...@west.net - 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). - 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: Medical Device Directive, IEC 601-1-2, and IEC 1000-3-2
Pat: 61000-3-2 is a horizontal standard and it applies to all products unless specifically excluded by 61000-3-2. The criteria is defined by CENELEC and it is not necessarily specified by the individual product standards. This is why it is so important to watch basic and horizontal standards even though they may not called out in the product standards. These cross-the-board standards are sleepers and can effect manufacturer's through the back door. Industry has decided to fight 61000-3-2 in the IEC and try to achieve realistic requirements. The US national committee has just released a position paper on harmonics requirements. If anyone needs a copy I can post it on this net. Dave George Unisys -Original Message- From: plaw...@west.net [mailto:plaw...@west.net] Sent: Thursday, June 17, 1999 7:55 PM To: emc-p...@majordomo.ieee.org Subject: Medical Device Directive, IEC 601-1-2, and IEC 1000-3-2 I was asked the following question, and wasn't sure about the answer: 1) A manufacturer can claim his system complies with the Medical Device Directive by testing to EN 60601-1-2:1993. 2) EN 60601-1-2:1993 does not have any requirements to test to IEC 1000-3-2. 3) Does that mean that the harmonic standard does not apply to this system when it becomes mandatory in 2001? I realize the Second Edition of IEC60601-1-2 is just around the corner, and that edition _does_ call out the harmonic test. However, I've been told that it may not take effect until 2003. -- Patrick Lawler plaw...@west.net - 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).
Re: Fw: Medical Device Directive, IEC 601-1-2, and IEC 1000-3-2
On Fri, 18 Jun 1999 09:25:51 -0800, Jon Griver wrote: From: Jon Griver jgri...@itl.co.il Subject: Medical Device Directive, IEC 601-1-2, and IEC 1000-3-2 Date: Fri, 18 Jun 1999 14:52:16 +0300 To: emc-p...@majordomo.ieee.org Patrick, 1) EN 60601-1-2 just covers EMC, while the scope the Medical Devices Directive includes safety, risk analysis, medical efficacy, biocompatibily, software validation, etc. My job responsibilities involve EMC, so I tend to have narrow focus. Should the original sentence should have read: A manufacturer can claim his system complies with the Medical Device Directive by testing to EN 60601-1. I think EN 60601-1 Amendment 1 includes the reference to EN 60601-1-2. Medical products are classified into Classes, 1, 11a, 11b and 111. Self declaration can be used for most, but not all, Class 1 products (the least critical). Even this this case, self declaration is based on a technical file that includes much more than EN 60601-1-2. In all other cases, approval is via a Notified Body under the Medical Devices Directive. Approval covers the manufacturer as well as the product, as some level of ISO 9000 approval is required. The ISO 9000 audit is carried out by the Notified Body itself. There is a complex relationship between the Class of product and the level of ISO 9000 approval required. 2) EN 60601-1-2 does have ESD requirements, but to IEC 801-2, which is older than IEC 1000-3-2. 3) EMC requirements for medical equipment are covered by the Medical Devices Directive, not the EMC Directive. So if harmonics are not mentioned in EN 60601-1-2, then it is not required. Jon Griver ITL (Product Testing) Ltd. http://www.itl.co.il I was asked the following question, and wasn't sure about the answer: 1) A manufacturer can claim his system complies with the Medical Device Directive by testing to EN 60601-1-2:1993. 2) EN 60601-1-2:1993 does not have any requirements to test to IEC 1000-3-2. 3) Does that mean that the harmonic standard does not apply to this system when it becomes mandatory in 2001? I realize the Second Edition of IEC60601-1-2 is just around the corner, and that edition _does_ call out the harmonic test. However, I've been told that it may not take effect until 2003. -- Patrick Lawler plaw...@west.net - 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). ---End of Original Message- -- Ed Price ed.pr...@cubic.com Electromagnetic Compatibility Lab Cubic Defense Systems San Diego, CA. USA 619-505-2780 Date: 06/18/1999 Time: 09:25:53 Military Avionics EMC Services Our Specialty Also Environmental / Metrology / Reliability -- Patrick Lawler plaw...@west.net - 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).
Fw: Medical Device Directive, IEC 601-1-2, and IEC 1000-3-2
Posted for Jon Griver: From: Jon Griver jgri...@itl.co.il Subject: Medical Device Directive, IEC 601-1-2, and IEC 1000-3-2 Date: Fri, 18 Jun 1999 14:52:16 +0300 To: emc-p...@majordomo.ieee.org Patrick, 1) EN 60601-1-2 just covers EMC, while the scope the Medical Devices Directive includes safety, risk analysis, medical efficacy, biocompatibily, software validation, etc. Medical products are classified into Classes, 1, 11a, 11b and 111. Self declaration can be used for most, but not all, Class 1 products (the least critical). Even this this case, self declaration is based on a technical file that includes much more than EN 60601-1-2. In all other cases, approval is via a Notified Body under the Medical Devices Directive. Approval covers the manufacturer as well as the product, as some level of ISO 9000 approval is required. The ISO 9000 audit is carried out by the Notified Body itself. There is a complex relationship between the Class of product and the level of ISO 9000 approval required. 2) EN 60601-1-2 does have ESD requirements, but to IEC 801-2, which is older than IEC 1000-3-2. 3) EMC requirements for medical equipment are covered by the Medical Devices Directive, not the EMC Directive. So if harmonics are not mentioned in EN 60601-1-2, then it is not required. Jon Griver ITL (Product Testing) Ltd. http://www.itl.co.il I was asked the following question, and wasn't sure about the answer: 1) A manufacturer can claim his system complies with the Medical Device Directive by testing to EN 60601-1-2:1993. 2) EN 60601-1-2:1993 does not have any requirements to test to IEC 1000-3-2. 3) Does that mean that the harmonic standard does not apply to this system when it becomes mandatory in 2001? I realize the Second Edition of IEC60601-1-2 is just around the corner, and that edition _does_ call out the harmonic test. However, I've been told that it may not take effect until 2003. -- Patrick Lawler plaw...@west.net - 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). ---End of Original Message- -- Ed Price ed.pr...@cubic.com Electromagnetic Compatibility Lab Cubic Defense Systems San Diego, CA. USA 619-505-2780 List-Post: emc-pstc@listserv.ieee.org Date: 06/18/1999 Time: 09:25:53 Military Avionics EMC Services Our Specialty Also Environmental / Metrology / Reliability -- - 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).
Fw: ITE Equipment installed in hospitals
Posted for Jon Griver: From: Jon Griver jgri...@itl.co.il Subject: ITE Equipment installed in hospitals Date: Fri, 18 Jun 1999 14:30:42 +0300 To: emc-p...@majordomo.ieee.org Charles, There should not be any problem using ITE equipment in hospitals, when the equipment is used by staff and nowhere near patients, and not connected to any other medical equipment. If ITE equipment is connected to medical equipment, then its use is covered by the standard IEC 601-1-1 (no, there are not too many 1's), for medical SYSTEMS. Basically, if the equipment is located outside of the 'patient vicinity' (see the standard for definition), then it only needs to comply with IEC 950. If it is located in the 'patient vicinity', then it must comply with IEC 601-1, for medical EQUIPMENT. In both cases, check IEC 601-1-1 to see how the equipment is connected, particularly with regard to grounding. Regards, Jon Griver ITL (Product Testing) Ltd. http://www.itl.co.il Does anyone know if ITE equipment is required to meet any Medical requirements if installed in a hospital. (No patient connections!!) Thank you Charles Grasso StorageTek 2270 Sth 88th Street Louisville CO 80027 Tel: (303)673-2908 Fax(303)661-7115 - 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). ---End of Original Message- -- Ed Price ed.pr...@cubic.com Electromagnetic Compatibility Lab Cubic Defense Systems San Diego, CA. USA 619-505-2780 List-Post: emc-pstc@listserv.ieee.org Date: 06/18/1999 Time: 09:12:51 Military Avionics EMC Services Our Specialty Also Environmental / Metrology / Reliability -- - 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).
Medical Device Directive, IEC 601-1-2, and IEC 1000-3-2
Patrick, In my previous answer, please ignore item 2. I misread IEC 1000-3-2 for IEC 1000-4-2. Jon Patrick, 1) EN 60601-1-2 just covers EMC, while the scope the Medical Devices Directive includes safety, risk analysis, medical efficacy, biocompatibily, software validation, etc. Medical products are classified into Classes, 1, 11a, 11b and 111. Self declaration can be used for most, but not all, Class 1 products (the least critical). Even this this case, self declaration is based on a technical file that includes much more than EN 60601-1-2. In all other cases, approval is via a Notified Body under the Medical Devices Directive. Approval covers the manufacturer as well as the product, as some level of ISO 9000 approval is required. The ISO 9000 audit is carried out by the Notified Body itself. There is a complex relationship between the Class of product and the level of ISO 9000 approval required. 2) EN 60601-1-2 does have ESD requirements, but to IEC 801-2, which is older than IEC 1000-3-2. 3) EMC requirements for medical equipment are covered by the Medical Devices Directive, not the EMC Directive. So if harmonics are not mentioned in EN 60601-1-2, then it is not required. Jon Griver ITL (Product Testing) Ltd. http://www.itl.co.il I was asked the following question, and wasn't sure about the answer: 1) A manufacturer can claim his system complies with the Medical Device Directive by testing to EN 60601-1-2:1993. 2) EN 60601-1-2:1993 does not have any requirements to test to IEC 1000-3-2. 3) Does that mean that the harmonic standard does not apply to this system when it becomes mandatory in 2001? I realize the Second Edition of IEC60601-1-2 is just around the corner, and that edition _does_ call out the harmonic test. However, I've been told that it may not take effect until 2003. -- Patrick Lawler plaw...@west.net - 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).
Re: NEAR/ FAR FIELD CORRELATION ISSUES
Even now, correlation between 3 meters and 10 meters is not guaranteed. And further, 3 meter to 10 meter correlation is at least better (define better anyway you wish) in the horizontal. Vertically it's terrible (define terrible anyway you wish). At least in my experience. Doug, In our 3m chamber we use a Vertical Correction Factor (VCF) to account for the worst-case difference between 3m and 10m vertical Radiated Emissions measurements. We usually have +/-1dB correlation, occasionally out to +/-2dB, between measurements taken in the chamber at 3m including the VCF against official measurements taken on our 10m Open Air Test Site (OATS). We also sometimes have some measurements taken at 10m that are much better than what we predicted at 3m with VCF, meaning that we have over-engineered the product in trying to ensure that we will pass the 10m tests... The VCF is more pessimistic than the 10m CISPR limits by: * About 1dB at 30MHz, increasing to * About 7.5dB at 230MHz, dropping to * About 0dB at 450MHz and above. As I understand it, the VCF was calculated by modelling: * A transmitting dipole antenna 1m above the groundplane with a receiving antenna 3m away, at 1m to 1.7m above the groundplane (the range of available heights in our 3m chamber) VERSUS * A transmitting dipole antenna 1m above the groundplane with a receiving antenna 10m away, at 1m to 4m above the groundplane (the range of heights required by CISPR testing). maximum received signal at 10m at f MHz 10^2 VCF (f MHz) = - * -- maximum received signal at 3m at f MHz3^2 In the far field we expect the signal to drop off at 1/r^2. But for vertically-polarized signals the receiving antenna sees not only a direct-path signal but one bounced off the groundplane. These two can add to double the voltage at the receiving antenna, or subtract to nearly zero, depending on the phase difference between the two paths. Running the antenna up and down helps get away from the worst nulls, but doesn't compensate for them completely. Considering that the actual source of the radiation may be at various heights or angles, not centered on the table, and the signal may reflect off other metal pieces, the Vertical Correction Factor is a huge help to us in trying to meet the Radiated Emissions limits. John Barnes Advisory Engineer Lexmark International dmckean%corp.auspex@interlock.lexmark.com on 06/17/99 04:39:53 PM Please respond to dmckean%corp.auspex@interlock.lexmark.com To: emc-pstc%majordomo.ieee@interlock.lexmark.com cc:(bcc: John Barnes/Lex/Lexmark) Subject: Re: NEAR/ FAR FIELD CORRELATION ISSUES At 11:18 AM 6/17/99 +1000, you wrote: Greetings and Salutations! I was wondering if this could be mailed out via the epc-pstc channels. I want to know if anyone is doing any work in near/ far field correlation to commercial EMC standard limits area and possibly correspond with them with a view to exchanging notes. Hi Arun, At a former company I spent a very large amount of time trying to correlate near field probe measurements of the surface currents and voltages of a product to far field (10 meter) measurements. In brief - it didn't happen. And a product could be analyzed as being constructed of a variety of antennas - slots, corner reflectors, tuned cavity, tuned arrays, and either electric or magnetic dipoles ... each reacting it's own way in the far field. Now I'm not going to say it's impossible, but it seems to me that one must assume something to begin with instead of being able to blindly take a surface current measurement or near field measurement of X and state confidently that it WILL be Y in the far field under all circumstances. That's ultimately what one would have to be able to do without regard to the product. After a few rounds with a particular product, I've done this. I'm sure everyone at some point has done this. But with NO prior history of the product, I don't see how it's done. Regards, Doug McKean - 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).
RE: NEAR/ FAR FIELD CORRELATION ISSUES
I remember many discussions on different CISPR Subcommittees on Swiss and Sweden's proposals and numerous papers presented on EMC Symposia in eighties and early nineties to replace OATS with absorbing clamp type measurements or to add clamp method as the alternative. All these proposals were rejected. Keep in mind that correlation between two good, acceptable 'reference' OATS using the same measurement distance is not that great, could be as poor as 8 dB just due to a NSA deviation. How much more dB would be acceptable, that is the question. I wish you and other EMC test method developers throughout the world good luck and success in developing acceptable alternative method to OATS. Mirko Matejic - 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: ITE Equipment installed in hospitals
There is no legal requirement, but the customer may ask for it. -- From: Grasso, Charles (Chaz) [SMTP:gra...@louisville.stortek.com] Sent: Thursday, June 17, 1999 9:58 PM To: 'EMC Group' Subject: ITE Equipment installed in hospitals Does anyone know if ITE equipment is required to meet any Medical requirements if installed in a hospital. (No patient connections!!) Thank you Charles Grasso StorageTek 2270 Sth 88th Street Louisville CO 80027 Tel: (303)673-2908 Fax(303)661-7115 - 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).
Re: NEAR/ FAR FIELD CORRELATION ISSUES
Hi, all You are absolutely right about correlation issues at 3 m/10 m, which arise predominantly from near field effects/ mutual coupling which is best demarcated from the far field by the equation 2*D*exp 2/lambada. Depending on the size of the object under test, the 3/10 m correlation, particularly in the frequency range say 30-100MHz could be out by as much as 5-6 dB (Remember the Mutual Impedance Correction Factors in Table G4 of CISPR 16-1, they were supposed to fix Site Attenuation defects at 3 metres !!). A baseline with some of the less complex artifacts would provide some assistance. Pauls Cook is right in saying that both E and H fields ought to be measured and mutual coupling effects between loop and object under test be accounted.(ie. the effect of the measurement transducer on the EUT) I have recently been quite puzzled by CISPR 11: 1992, when they quoted that below 30MHz the quasi-peak limits refer to the magnetic component of electromagnetic radiation. Contrary to this the limits are specified in dBuV/m instead of dBuA/m (Group 2 Class A, Table 5)!! Now, Because of the frequencies, test object sizes and test distance lengths involved I cannot invoke the golden 120*pi rule and make the conversion. But, is this what is expected of a test house? Also, ITE frequencies have shot past 500MHz, is an equivalent CISPR 22 frequency upgrade in the pipeline? Arun Kaore EMC Engineer ADI Limited Systems Group Test Evaluation Centre Forrester Road, St Marys, NSW 2760 P O Box: 315, St Marys NSW 1790 Tel: 61 2 9673 8375 Fax: 61 2 9673 8321 Email: kao...@sg.adi-limited.com.au -Original Message- From: Douglas McKean [SMTP:dmck...@corp.auspex.com] Sent: Friday, 18 June, 1999 6:40 To: emc-p...@majordomo.ieee.org Subject: Re: NEAR/ FAR FIELD CORRELATION ISSUES At 11:18 AM 6/17/99 +1000, you wrote: Even now, correlation between 3 meters and 10 meters is not guaranteed. And further, 3 meter to 10 meter correlation is at least better (define better anyway you wish) in the horizontal. Vertically it's terrible (define terrible anyway you wish). At least in my experience. And a product could be analyzed as being constructed of a variety of antennas - slots, corner reflectors, tuned cavity, tuned arrays, and either electric or magnetic dipoles ... each reacting it's own way in the far field. Now I'm not going to say it's impossible, but it seems to me that one must assume something to begin with instead of being able to blindly take a surface current measurement or near field measurement of X and state confidently that it WILL be Y in the far field under all circumstances. That's ultimately what one would have to be able to do without regard to the product. After a few rounds with a particular product, I've done this. I'm sure everyone at some point has done this. But with NO prior history of the product, I don't see how it's done. Regards, Doug McKean - 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: NEAR/ FAR FIELD CORRELATION ISSUES
I also wish you great luck. Two major issues will confound you: 1) To convert a near field measurment to the far field, by definition you need to know the wave impedance of the source. We know that in the far field, the wave impedance will have become 377 ohms, but in the near field it may thousands of ohms from an electric field source, or it may be tens of ohms from a magnetic field source. With measurments from a loop probe, you are measuring only the magnetic field component, and you will have trouble doing the extrapolation to the far field. Once you have solved this problem, its closely related cousin lurks for you in the darkness. 2) The cousin: Antennas like dipoles and biconicals produce a voltage that is related to the electromagnetic field in the vicinity of the antenna. That field in turn is generated by the EUT, and the strength of that field is determined by two factors, the current flowing in the radiating element, and the geometry of the radiating element (its length/area). A small loop probe produces a voltage that is only proportional to the current flowing in the radiating structure. Thus to calculate the farfield effects of the current you need to be continually moving the loop probe and doing line integrals and area integrals. PS If those two dont get you, I've always had a sneaking suspicion that the process of making nearfield loop probe measurements can affect the emissions coming from an EUT, but I've never actually tried to prove it. Anyways, good luck is in order, but I won't be holding my breath. Paul Cook NARTE Certified EMC Engineer Alpha EMC Inc 8540 West River Rd Minneapolis, Minnestoa 55444 Tel # (612)-561-2844 Fax #(612)-561-3400 E-mailpaulc...@skypoint.com Specialty - EMC Consulting -Original Message- From: Arun Kaore kao...@sg.adi-limited.com.au To: 'emc-p...@majordomo.ieee.org' emc-p...@majordomo.ieee.org List-Post: emc-pstc@listserv.ieee.org Date: Wednesday, June 16, 1999 11:58 PM Subject: NEAR/ FAR FIELD CORRELATION ISSUES Greetings and Salutations! I was wondering if this could be mailed out via the epc-pstc channels. I want to know if anyone is doing any work in near/ far field correlation to commercial EMC standard limits area and possibly correspond with them with a view to exchanging notes. Brief Follows: Brief: Application of Near Field and possibly Surface probe techniques in Evaluating Emissions from source equipment and correlating/quantifying this data to an OATS, LISN, Absorbing Clamp etc based measurement.. Details: We assume that the current EMC compliance regime around the world has quantified limits of compliance to which if every source equipment adheres to, then it has a reasonable chance of performing as intended in a real life situation, noting that the immunity threshold test levels are much more stringent than EM emission limits. Current EMC measurements are very cumbersome, require large expense in setting up and maintaining (calibrating) OATS, LISNS, Absorbing Clamps, Ferrite tiled lined semi- anechoics etc. Despite this expense, the measurement uncertainities are still of the order of 6 to 10dB (inherent). Every newly released EMC standard by IEC CISPR or CENELEC has potentially new transducers and new headaches from point of view of sourcing and maintenance, calibration. EMC today is where Safety was 10 years ago. I am of the opinion that EMC testing should be simplified and reasonably accessible to all end users. Continued progress and urban development has led to increasing levels of broad and narrowband noise to the extent that ambient profiles sometimes swamp out the limits; this has led to most test houses in the EU to opt for GTEMS or semi-anechoics (referred to as alternative all weather test sites) at considerable expense. Current techniques such as emission E Field prescanning in shielded rooms prior to OATS based testing with biconilog antennae have the drawbacks of peaking the emissions and reflections/standing waves. Hence: I propose to develop near or surface probe H (inverse of E) field techniques which actually senses the emission profiles and correlate them to an Absorber clamp, or OATS or LISN (Common mode fix) or whatever. Cables, panels, slots etc could be sniffed with a Loop and if it is possible to correlate this near or induction field data to compliance limits then it becomes very easy for individuals and organisations to do precertification. Transducers could be simple and light weight, rugged, and physically defined so that minimal calibration is required. EMI receivers will still need calibration. With these techniques, you measure actually what comes off the source and not the peak value of the bounced and direct rays within say the Fresnel ellipse, or move the Absorbing clamp up and down the rail and peak the field. Conducted emissions could be scanned by common mode techniques and radiated emissions by surface or near scans. Currently, these techniques are
ITE Equipment installed in hospitals
Does anyone know if ITE equipment is required to meet any Medical requirements if installed in a hospital. (No patient connections!!) Thank you Charles Grasso StorageTek 2270 Sth 88th Street Louisville CO 80027 Tel: (303)673-2908 Fax(303)661-7115 - 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).
Medical Device Directive, IEC 601-1-2, and IEC 1000-3-2
I was asked the following question, and wasn't sure about the answer: 1) A manufacturer can claim his system complies with the Medical Device Directive by testing to EN 60601-1-2:1993. 2) EN 60601-1-2:1993 does not have any requirements to test to IEC 1000-3-2. 3) Does that mean that the harmonic standard does not apply to this system when it becomes mandatory in 2001? I realize the Second Edition of IEC60601-1-2 is just around the corner, and that edition _does_ call out the harmonic test. However, I've been told that it may not take effect until 2003. -- Patrick Lawler plaw...@west.net - 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: Medical Device Directive, IEC 601-1-2, and IEC 1000-3-2
It is my understanding that 61000-3-2 is a family standard (at least that is what it says in the introduction of the copy that I have) and as such includes all equipment equal to or less than 16 amps. Bob Heller === === plaw...@west.net (Patrick Lawler) on 06/17/99 06:55:21 PM Please respond to plaw...@west.net (Patrick Lawler) To: emc-p...@majordomo.ieee.org cc:(bcc: Robert E. Heller/US-Corporate/3M/US) Subject: Medical Device Directive, IEC 601-1-2, and IEC 1000-3-2 I was asked the following question, and wasn't sure about the answer: 1) A manufacturer can claim his system complies with the Medical Device Directive by testing to EN 60601-1-2:1993. 2) EN 60601-1-2:1993 does not have any requirements to test to IEC 1000-3-2. 3) Does that mean that the harmonic standard does not apply to this system when it becomes mandatory in 2001? I realize the Second Edition of IEC60601-1-2 is just around the corner, and that edition _does_ call out the harmonic test. However, I've been told that it may not take effect until 2003. -- Patrick Lawler plaw...@west.net - 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).
RE: Near/ Far Field Correlation Issues
With regard to the CISPR 11 limits below 30 MHz. A magnetic loop measurement is made because the loop measurement is more accurate than an E-field measurement. The practice of converting the measurement to a far field equivalent electric field intenisty is purely an algebraic conversion. -Original Message- From: Arun Kaore [SMTP:kao...@sg.adi-limited.com.au] Sent: Thursday, June 17, 1999 11:42 PM To: 'emc-p...@majordomo.ieee.org' Subject: Re: Near/ Far Field Correlation Issues Hi, all You are absolutely right about correlation issues at 3 m/10 m, which arise predominantly from near field effects/ mutual coupling which is best demarcated from the far field by the equation 2*D*exp 2/lambada. Depending on the size of the object under test, the 3/10 m correlation, particularly in the frequency range say 30-100MHz could be out by as much as 5-6 dB (Remember the Mutual Impedance Correction Factors in Table G4 of CISPR 16-1, they were supposed to fix Site Attenuation defects at 3 metres !!). A baseline with some of the less complex artifacts would provide some assistance. Pauls Cook is right in saying that both E and H fields ought to be measured and mutual coupling effects between loop and object under test be accounted.(ie. the effect of the measurement transducer on the EUT) I have recently been quite puzzled by CISPR 11: 1992, when they quoted that below 30MHz the quasi-peak limits refer to the magnetic component of electromagnetic radiation. Contrary to this the limits are specified in dBuV/m instead of dBuA/m (Group 2 Class A, Table 5)!! Now, Because of the frequencies, test object sizes and test distance lengths involved I cannot invoke the golden 120*pi rule and make the conversion. But, is this what is expected of a test house? Also, ITE frequencies have shot past 500MHz, is an equivalent CISPR 22 frequency upgrade in the pipeline? Arun Kaore EMC Engineer ADI Limited Systems Group Test Evaluation Centre Forrester Road, St Marys, NSW 2760 P O Box: 315, St Marys NSW 1790 Tel: 61 2 9673 8375 Fax: 61 2 9673 8321 Email: kao...@sg.adi-limited.com.au -Original Message- From: Douglas McKean [SMTP:dmck...@corp.auspex.com] Sent: Friday, 18 June, 1999 6:40 To: emc-p...@majordomo.ieee.org Subject:Re: NEAR/ FAR FIELD CORRELATION ISSUES At 11:18 AM 6/17/99 +1000, you wrote: Even now, correlation between 3 meters and 10 meters is not guaranteed. And further, 3 meter to 10 meter correlation is at least better (define better anyway you wish) in the horizontal. Vertically it's terrible (define terrible anyway you wish). At least in my experience. And a product could be analyzed as being constructed of a variety of antennas - slots, corner reflectors, tuned cavity, tuned arrays, and either electric or magnetic dipoles ... each reacting it's own way in the far field. Now I'm not going to say it's impossible, but it seems to me that one must assume something to begin with instead of being able to blindly take a surface current measurement or near field measurement of X and state confidently that it WILL be Y in the far field under all circumstances. That's ultimately what one would have to be able to do without regard to the product. After a few rounds with a particular product, I've done this. I'm sure everyone at some point has done this. But with NO prior history of the product, I don't see how it's done. Regards, Doug McKean - 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).
