Re: Emissions "quick test"
I have used a little portable transistor radio for system sniffing of a system with low level freqs and with already knowing the problem freqs. Regards, Doug McKean --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list"
RE: Emissions "quick test"
>-Original Message- >From: lisa_cef...@mksinst.com [mailto:lisa_cef...@mksinst.com] >Sent: Tuesday, August 20, 2002 1:35 PM >To: emc-p...@majordomo.ieee.org >Subject: Emissions "quick test" > > > >Hi all, > >Does anyone know of a " down- and- dirty" , inexpensive method >or equipment >for sniffing out emissions issues? I've used a Spectrum >Analyzer in the >past with a series of different probes, but that tends to be >costly. Also, >Is there a "universal" probe kit out there? > >Thank you in advance. > >Lisa > >Lisa A. Cefalo, CRE >Manager, Reliability and Design Services >MKS Instruments >6 Shattuck Road >Andover, MA 01810 >(978)-975-2350 X 5669 >lisa_cef...@mksinst.com > > Lisa: You can make a fairly universal probe by winding three turns of stiff wire around your little finger. Remove finger and solder the coil to the end of female/female BNC connector. Connect probe to a spectrum analyzer and start probing. You can make another cheap probe by stripping about an inch of the outer conductor off the end of a piece of RG-223 coax. The dielectric will support the small stub of center conductor, and you get a nice, low sensitivity probe that you can drag over ribbon cable wires or board traces. A spectrum analyzer is about the minimum ticket needed for this ride. You could use a cheap AM radio, or a scanner, or a communications receiver, but interpreting the results is time consuming. You could use an analog oscilloscope for some probing, but you could get a low-end spectrum analyzer for the cost of a decent oscilloscope. You can buy an old spectrum analyzer, typically something like an HP-141/8552/8553 for well under $1000; just watch eBay for a couple of weeks. If you are extremely determined to avoid buying a spectrum analyzer, you might be interested in a classic Ham Radio project, called the Poor Man's Spectrum Analyzer. This project allowed you to build a spectrum analyzer using old television tuners, and is a testament to what can be accomplished with unlimited labor applied to analog junk. 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 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: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list"
Re: Emissions "quick test"
EMCO/ETS makes a probe kit with a preamp for under $1000. Several probes, E- and H-field. Electro-metrics makes the same kind of kit, but without the pre-amp, per my recollection. I think Com-power might also do this kind of thing, and be the low price vendor as well. If the EUT is noisy and you are in very close, you might be able to see something on an oscilloscope, but clearly it will a low-passed time domain waveform which you cannot correlate well with measured OATS data. There are pre-compliance analyzers on the market for well under $5 K these days. on 8/20/02 3:34 PM, lisa_cef...@mksinst.com at lisa_cef...@mksinst.com wrote: > > Hi all, > > Does anyone know of a " down- and- dirty" , inexpensive method or equipment > for sniffing out emissions issues? I've used a Spectrum Analyzer in the > past with a series of different probes, but that tends to be costly. Also, > Is there a "universal" probe kit out there? > > Thank you in advance. > > Lisa > > Lisa A. Cefalo, CRE > Manager, Reliability and Design Services > MKS Instruments > 6 Shattuck Road > Andover, MA 01810 > (978)-975-2350 X 5669 > lisa_cef...@mksinst.com > > > --- > This message is from the IEEE EMC Society Product Safety > Technical Committee emc-pstc discussion list. > > Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ > > To cancel your subscription, send mail to: > majord...@ieee.org > with the single line: > unsubscribe emc-pstc > > For help, send mail to the list administrators: > Ron Pickard: emc-p...@hypercom.com > Dave Heald: davehe...@attbi.com > > For policy questions, send mail to: > Richard Nute: ri...@ieee.org > Jim Bacher: j.bac...@ieee.org > > All emc-pstc postings are archived and searchable on the web at: > http://ieeepstc.mindcruiser.com/ > Click on "browse" and then "emc-pstc mailing list" > -- Ken Javor EMC Compliance Huntsville, Alabama 256/650-5261 --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list"
Re: Question on highest frequency used
Putting on my Master of the Obvious hat, I would say that I would expect that a 12 GHz receiver would generate some frequencies in excess of the 50 MHz DSP, for a local oscillator, say. But you shouldn't have to test to multiples of the LO frequency, since it is a clean cw signal. Testing up to the highest LO frequency ought to be sufficient. So I would say you should test up to 5X the clock frequency, and then also at frequencies that the LO can be tuned to. In fact, I believe there are special requirements to make sure LOs don't radiate out of receiver-connected antennas, right? on 8/20/02 11:23 AM, Grasso, Charles at charles.gra...@echostar.com wrote: > > Hi - and just when I thought I had it all > figured out.. > > I have a question on the FCC requirement to test > a product to the highest frequency used. > > Say a company has an RF receiver that has a > DSP processor in it running at 50MHz. Lets > also say that said receiver is pointed at a > transmitter that has a 12Ghz signal. > > Should I test the receiver to > a) 5X the 50MHz or > b) 5x the 12GHz transmitter signal? > > We have an FCC interpretation - bet you > can't guess what it is.. > > Charles Grasso > Senior Compliance Engineer > Echostar Technologies Corporation > phone: 303.706.5467 > FAX: 303.799.6222 > > Charles Grasso > Senior Compliance Engineer > Echostar Technologies Corporation > phone: 303.706.5467 > FAX: 303.799.6222 > > --- > This message is from the IEEE EMC Society Product Safety > Technical Committee emc-pstc discussion list. > > Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ > > To cancel your subscription, send mail to: > majord...@ieee.org > with the single line: > unsubscribe emc-pstc > > For help, send mail to the list administrators: > Ron Pickard: emc-p...@hypercom.com > Dave Heald: davehe...@attbi.com > > For policy questions, send mail to: > Richard Nute: ri...@ieee.org > Jim Bacher: j.bac...@ieee.org > > All emc-pstc postings are archived and searchable on the web at: > http://ieeepstc.mindcruiser.com/ > Click on "browse" and then "emc-pstc mailing list" > -- Ken Javor EMC Compliance Huntsville, Alabama 256/650-5261 --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list"
RE: Radiated Emissions setup
Worse arrangement obtainable within the prescribed set-up. e. g. peripherals 10 cm apart, equipment aligned with the table edge, and excess cable bundled above the ground plane et al as described in C63.4 and CISPR 22 (or 16?). There was a time when it was just plain worse arrangement. In that case you had an X factorial number of combinations to play with. CPU, mouse, printer, modem: cpu, printer, mouse, modem: cpu printer, modem mouse, et all. I'll be darned if I remember what all we had attached but it had 10 peripherals and that was a grand total of over 3 million combinations if one followed the directions literally. There also was the consultant who when called to the FCC test site to explain a test failure found that the FEDS had taken the keyboard cables and wrapped it around the monitor. An operator would have had to stare through the cables to read the screen.Heavy sigh! (Could just be urban legend but it matches a pattern in the beginning of commercial EMC measurements of 1982. Good people but a little overzealous at times. Gary -Original Message- From: michael.sundst...@nokia.com [mailto:michael.sundst...@nokia.com] Sent: Tuesday, August 20, 2002 12:56 PM To: robert.s...@flextronics.com; alex.mcn...@ingenicofortronic.com; emc-p...@majordomo.ieee.org Subject: RE: Radiated Emissions setup The cable layout is required to be the 'worst case' attainable, isn't it? Michael Sundstrom NOKIA TCC Dallas / EMC ofc: (972) 374-1462 cell: (817) 917-5021 amateur call: KB5UKT -Original Message- From: ext robert.s...@flextronics.com [mailto:robert.s...@flextronics.com] Sent: Tuesday, August 20, 2002 1:05 PM To: alex.mcn...@ingenicofortronic.com; emc-p...@majordomo.ieee.org Subject: RE: Radiated Emissions setup Neil, I would like to see the pictures of your audit board. Without seeing the pictures I have the following comments. 1. I think this is a very good idea from a repeatability standpoint and I would like to consider adopting it. 2. It may be more trouble than simply draping the cables over the table edge, but less than bundling them properly. 3. Some of our customers bring their products in already attached to such a board with their cables all fastened securely in configurations accepted by their customers. This also lessens the setup time and gets them in and out quicker. 4. I believe that Note 1 of Figure 10 in EN 55022 refers to cables which connect one piece of gear on the table to another. If the cables were cut, it would require splicing or installing connectors. If a shorter cable were used, it may not represent actual use. I feel that generally customers having a two meter cable which is longer than needed would either drape it to the floor (which is not normally a metal ground plane), or bundle it neatly to keep it out of the way. On the other hand, since we as testers never know how equipment will be configured, the demand for repeatability requires that a system such as that described in Figure 10 be used. Robert Seay -Original Message- From: Alex McNeil [mailto:alex.mcn...@ingenicofortronic.com] Sent: Tuesday, August 20, 2002 12:00 PM To: 'emc-p...@majordomo.ieee.org' Subject:Radiated Emissions setup Hi Forum, As we all know test setups are absolutely critical to EMC results. I have the good fortune of having a good pre-compliance radiated emissions site (3m OATS, Fully or Semi Anechoic Chamber). From using this site I see all sorts of "funnies" but still the most annoying is how much you can change the emission results just by changing cable positions. I carry out regular EMC audits and could never quite get the same results as 6 months previous, when that particular product was last tested (I keep the master product and was still getting different results due to setup). I now use an "Audit" board where I bundle the cables (30-40cm) in a particular "figure of 8" fashion via fixed wooden pegs. Thru' time I have convinced myself that this not only gives me worst case emissions but also that much sought after REPEATABILITY! I believe the setup is as per EN55022. I have a photograph* of this Audit board to allow this forum to comment on the good and the bad points of using such a system. Also, is there any reason I cannot take this Audit board to a Test House for Product Compliance testing and at the same time get correlation between a Compliance site and my own site? Photograph details (EUT with 3 X Serial Ports, PSTN and DC SELV power connection) 1. The 1M, 2M and 3M indicate the Horizontal bundling of cables from RS232 ports which would go to a tabletop EUT peripheral (or leave open circuit). The 3 lengths are connected to similar ports. This covers the different lengths issues. 2. The P is the inline power supply O/P cable going to the EUT. This is bundled vertically as it represents the power supply sitting on a customers floor. 3.
Re: EN6100 3 2 1998 repeatability test
I read in !emc-pstc that Gary McInturff wrote (in <917063bab0ddb043af5faa73c7a835d40ac...@windlord.wwp.com >) about 'EN6100 3 2 1998 repeatability test', on Mon, 19 Aug 2002: >This is the harmonics test. > The 1998 version which goes into effect about 2004 has a clause that >says the test has to be run twice and the results compared. It helps a great deal if you give the clause number of any requirement that you question. Do you mean 6.2.3.1 in this case? > The comparison seems >to be fairly restrictive from what I am hearing, and a number of failures >being >reported because they two runs, while within specifications individually do >not >compare exactly with each other. One of the harmonics might be 6% different >than >the other and this causes a test failure. I'm quite sure that 6.2.3.1. is NOT intended to mean that, but I didn't write it. I will pass this question to the people who did. For the higher harmonics, certainly above the 21st, quite large variations between test runs can occur for no apparent reason. Provided no limits are exceeded, these variations are of no significance. > Can anybody comment with more knowledge of what is happening and > whether >or not this is causing a review of this requirement? I haven't heard of this problem before. It has not been previously raised in IEC SC77A/WG1, and members have now asked if you can be more definite about what equipment was rejected and if possible, by whom. You may send that information to me by e-mail as it may be sensitive. -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk Interested in professional sound reinforcement and distribution? Then go to http://www.isce.org.uk PLEASE do NOT copy news posts to me by E-MAIL! --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list"
RE: Question on highest frequency used - and the consensus is..
We need to test to 40GHz. Oh boy.. -Original Message- From: am...@westin-emission.no [mailto:am...@westin-emission.no] Sent: Tuesday, August 20, 2002 2:02 PM To: emc-p...@majordomo.ieee.org Subject: SV: Question on highest frequency used I guess 5x12GHz I was told a few years ago " the highest existing frequency in the equipment/system...". You better buy a new analyser which covers up to 60Gig... :-) Best regards Amund, Oslo/Norway > -Opprinnelig melding- > Fra: owner-emc-p...@majordomo.ieee.org > [mailto:owner-emc-p...@majordomo.ieee.org]På vegne av Grasso, Charles > Sendt: 20. august 2002 18:23 > Til: 'emc-p...@majordomo.ieee.org' > Emne: Question on highest frequency used > > > > Hi - and just when I thought I had it all > figured out.. > > I have a question on the FCC requirement to test > a product to the highest frequency used. > > Say a company has an RF receiver that has a > DSP processor in it running at 50MHz. Lets > also say that said receiver is pointed at a > transmitter that has a 12Ghz signal. > > Should I test the receiver to > a) 5X the 50MHz or > b) 5x the 12GHz transmitter signal? > > We have an FCC interpretation - bet you > can't guess what it is.. > > Charles Grasso > Senior Compliance Engineer > Echostar Technologies Corporation > phone: 303.706.5467 > FAX: 303.799.6222 > > Charles Grasso > Senior Compliance Engineer > Echostar Technologies Corporation > phone: 303.706.5467 > FAX: 303.799.6222 > > --- > This message is from the IEEE EMC Society Product Safety Technical > Committee emc-pstc discussion list. > > Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ > > To cancel your subscription, send mail to: > majord...@ieee.org > with the single line: > unsubscribe emc-pstc > > For help, send mail to the list administrators: > Ron Pickard: emc-p...@hypercom.com > Dave Heald: davehe...@attbi.com > > For policy questions, send mail to: > Richard Nute: ri...@ieee.org > Jim Bacher: j.bac...@ieee.org > > All emc-pstc postings are archived and searchable on the web at: > http://ieeepstc.mindcruiser.com/ > Click on "browse" and then "emc-pstc mailing list" --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list" --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list"
Emissions "quick test"
Hi all, Does anyone know of a " down- and- dirty" , inexpensive method or equipment for sniffing out emissions issues? I've used a Spectrum Analyzer in the past with a series of different probes, but that tends to be costly. Also, Is there a "universal" probe kit out there? Thank you in advance. Lisa Lisa A. Cefalo, CRE Manager, Reliability and Design Services MKS Instruments 6 Shattuck Road Andover, MA 01810 (978)-975-2350 X 5669 lisa_cef...@mksinst.com --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list"
SV: Question on highest frequency used
I guess 5x12GHz I was told a few years ago " the highest existing frequency in the equipment/system...". You better buy a new analyser which covers up to 60Gig... :-) Best regards Amund, Oslo/Norway > -Opprinnelig melding- > Fra: owner-emc-p...@majordomo.ieee.org > [mailto:owner-emc-p...@majordomo.ieee.org]På vegne av Grasso, Charles > Sendt: 20. august 2002 18:23 > Til: 'emc-p...@majordomo.ieee.org' > Emne: Question on highest frequency used > > > > Hi - and just when I thought I had it all > figured out.. > > I have a question on the FCC requirement to test > a product to the highest frequency used. > > Say a company has an RF receiver that has a > DSP processor in it running at 50MHz. Lets > also say that said receiver is pointed at a > transmitter that has a 12Ghz signal. > > Should I test the receiver to > a) 5X the 50MHz or > b) 5x the 12GHz transmitter signal? > > We have an FCC interpretation - bet you > can't guess what it is.. > > Charles Grasso > Senior Compliance Engineer > Echostar Technologies Corporation > phone: 303.706.5467 > FAX: 303.799.6222 > > Charles Grasso > Senior Compliance Engineer > Echostar Technologies Corporation > phone: 303.706.5467 > FAX: 303.799.6222 > > --- > This message is from the IEEE EMC Society Product Safety > Technical Committee emc-pstc discussion list. > > Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ > > To cancel your subscription, send mail to: > majord...@ieee.org > with the single line: > unsubscribe emc-pstc > > For help, send mail to the list administrators: > Ron Pickard: emc-p...@hypercom.com > Dave Heald: davehe...@attbi.com > > For policy questions, send mail to: > Richard Nute: ri...@ieee.org > Jim Bacher: j.bac...@ieee.org > > All emc-pstc postings are archived and searchable on the web at: > http://ieeepstc.mindcruiser.com/ > Click on "browse" and then "emc-pstc mailing list" --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list"
RE: Radiated Emissions setup
The cable layout is required to be the 'worst case' attainable, isn't it? Michael Sundstrom NOKIA TCC Dallas / EMC ofc: (972) 374-1462 cell: (817) 917-5021 amateur call: KB5UKT -Original Message- From: ext robert.s...@flextronics.com [mailto:robert.s...@flextronics.com] Sent: Tuesday, August 20, 2002 1:05 PM To: alex.mcn...@ingenicofortronic.com; emc-p...@majordomo.ieee.org Subject: RE: Radiated Emissions setup Neil, I would like to see the pictures of your audit board. Without seeing the pictures I have the following comments. 1. I think this is a very good idea from a repeatability standpoint and I would like to consider adopting it. 2. It may be more trouble than simply draping the cables over the table edge, but less than bundling them properly. 3. Some of our customers bring their products in already attached to such a board with their cables all fastened securely in configurations accepted by their customers. This also lessens the setup time and gets them in and out quicker. 4. I believe that Note 1 of Figure 10 in EN 55022 refers to cables which connect one piece of gear on the table to another. If the cables were cut, it would require splicing or installing connectors. If a shorter cable were used, it may not represent actual use. I feel that generally customers having a two meter cable which is longer than needed would either drape it to the floor (which is not normally a metal ground plane), or bundle it neatly to keep it out of the way. On the other hand, since we as testers never know how equipment will be configured, the demand for repeatability requires that a system such as that described in Figure 10 be used. Robert Seay -Original Message- From: Alex McNeil [mailto:alex.mcn...@ingenicofortronic.com] Sent: Tuesday, August 20, 2002 12:00 PM To: 'emc-p...@majordomo.ieee.org' Subject:Radiated Emissions setup Hi Forum, As we all know test setups are absolutely critical to EMC results. I have the good fortune of having a good pre-compliance radiated emissions site (3m OATS, Fully or Semi Anechoic Chamber). From using this site I see all sorts of "funnies" but still the most annoying is how much you can change the emission results just by changing cable positions. I carry out regular EMC audits and could never quite get the same results as 6 months previous, when that particular product was last tested (I keep the master product and was still getting different results due to setup). I now use an "Audit" board where I bundle the cables (30-40cm) in a particular "figure of 8" fashion via fixed wooden pegs. Thru' time I have convinced myself that this not only gives me worst case emissions but also that much sought after REPEATABILITY! I believe the setup is as per EN55022. I have a photograph* of this Audit board to allow this forum to comment on the good and the bad points of using such a system. Also, is there any reason I cannot take this Audit board to a Test House for Product Compliance testing and at the same time get correlation between a Compliance site and my own site? Photograph details (EUT with 3 X Serial Ports, PSTN and DC SELV power connection) 1. The 1M, 2M and 3M indicate the Horizontal bundling of cables from RS232 ports which would go to a tabletop EUT peripheral (or leave open circuit). The 3 lengths are connected to similar ports. This covers the different lengths issues. 2. The P is the inline power supply O/P cable going to the EUT. This is bundled vertically as it represents the power supply sitting on a customers floor. 3. The T is the PSTN telecomms cable. Again bundled vertically as it represents the cable going from the EUT to the wall socket. Finally, I have never understood the EN55022 figure 10 note 1 "If cables which hang closer than 40cm to the horizontal ground plane cannot be shortened to appropriate length, the excess shall be folded back and forth forming a bundle 30cm to 40cm long". Does this mean you can cut the cable to 1m or ? even though you will be shipping say 2m cables with the product? *I have not attached the photograph, 212Kb. This will be sent to those requesting it i.e. to those people who are thinking of commenting on this email. I look forward with interest to this forums comments. Kind Regards Alex McNeil Principal Engineer Tel: +44 (0)131 479 8375 Fax: +44 (0)131 479 8321 email: alex.mcn...@ingenicofortronic.com --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee
RE: EN 55022:1998 vs. ANSI C63.4
Hi Steven The function of the ferrites to prevent noise to enter the site is just one side of the story. One equally important aspect is presenting a fixed Common Mode impedance (150 Ohm approx)to the interference current sources that drive the cables and to create a fixed radiating cable length. Both for reproducibility. One will definitely find less resonances due to cabling using the CISPR set up both down- and upwards as using the ANSI set up. Therefore I suggest to re test. Gert Gremmen ce-test, qualified testing http://www.cetest.nl -Original Message- From: owner-emc-p...@majordomo.ieee.org [mailto:owner-emc-p...@majordomo.ieee.org]On Behalf Of Steven Goulding Sent: dinsdag 20 augustus 2002 19:03 To: jim.hulb...@pb.com; emc-p...@ieee.org Subject: Re: EN 55022:1998 vs. ANSI C63.4 The idea of putting the ferrites on the cables is to prevent noise from outside the test site form entering the test site. My opinion is that you should not have to repeat the test as the ferrites do not have any effect on what is happening in the room where the test is being performed. Just one mans opinion. Steven - Original Message - From: To: Sent: Tuesday, August 20, 2002 9:16 AM Subject: EN 55022:1998 vs. ANSI C63.4 > > Probably won't get many responses this week as everyone with a travel > budget is now in Minnesota. However, I'll try it anyway. > > In the 1998 version of EN 55022, radiated emissions tests on table top > products are performed with a ferrite tube or clamp on each cable that > exits the test site (i.e. AC mains, telecom, I/O to remote control units). > ANSI C63.4 does not specify this. If I follow the EN 55022 procedure, is > it necessary to repeat without the ferrite clamps in order to satisfy the > ANSI test procedure? > > Thanks. > > Jim Hulbert > Pitney Bowes > > > --- > This message is from the IEEE EMC Society Product Safety > Technical Committee emc-pstc discussion list. > > Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ > > To cancel your subscription, send mail to: > majord...@ieee.org > with the single line: > unsubscribe emc-pstc > > For help, send mail to the list administrators: > Ron Pickard: emc-p...@hypercom.com > Dave Heald: davehe...@attbi.com > > For policy questions, send mail to: > Richard Nute: ri...@ieee.org > Jim Bacher: j.bac...@ieee.org > > All emc-pstc postings are archived and searchable on the web at: > http://ieeepstc.mindcruiser.com/ > Click on "browse" and then "emc-pstc mailing list" --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list" --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list"
RE: Radiated Emissions setup
A few loose comments and additions on your approach: The CISPR committee is like you seeking for repeatability in test set ups. Therefore an effort is made to create a common set up for immunity and emission test set up. The idea is a (vert) cylindric volume of 1m60 miniumum diameter for left and right cables to extend 80 cm and then leading 80 cm down to ground surface where each cable is clamped using an (yet) undefined ferrite clamp. (on rotating table) Several propositions are into the voting chain of which one is an amendment to CISPR 16-1. The 1m60 cylinder does not cope for EUT sizes, so in order to create a workable test setup 2 m cylinder is required and still allow for moderate EUT sizes. In addition to the 2 m cylinder a 1m distance to the walls of the FAR would be required, and sufficient distance is required to the antenna for it to "illuminate" the full cylinder. Calibration procedures are also in the propositions. However, a full compliant set up cannot be made in a 3 m room, due to size restrictions. Several aspects may however lead to substantial different radiations results as before: The fixed radiating lead length of 2 x 80 cm + ferrite behaving as 150 Ohms Common Mode load) makes the lead look like infinite to the EUT disturbanc voltage source (at least that's the idea). For frequencies below 1/2 lambda lead lenght ( 1m60 = 92 Mhz the wires (left + rigth) begin to behave like a shortened dipole with (of course) reduced emssions compared to real life where cables CAN be infinite. The procedure is now to find out in what combination of left right cable lay out creates maximum emissions. If you forget that, different phase steered cables may compensate emissions. Think of the cables as being current fed from a matrix of interference sources with arbitrary voltage where each cable is connected to a different point of the matrix and you get the idea. Just putting cables where you like is *not* sufficient. A FAR differs from an OATS in that no height variation of the antenna is required. For small sources or line radiating sources such as a dipole cable set (!!), the low frequency results may be up to 24 dB higher then at the OATS (with HOR polarization) this is due to the fact that on an OATS the reflected ground wave is in opposite phase and attenuates the incident wave. For this to compensate the hight variations were invented. travelling ways differ when rising and lowering the antenna until a maximum was found. Unfortunately at low frequencies one will never never rise the antenna as high as required for a full compensation of this effect. (I have a Mathcad 2001 model for those who want to experiment: infinite height would be required but signal topsat 15m). As there is no ground reflection in the FAR, the low frequency response is much better then on the OATS. Though antenna signal is 5 dB (theoretic 6) lower in a FAR because the absence of the reflected wave the effect of the insufficient OATS model are not accounted for. At vertical polarization this OATS effect does not happen as the reflected wave is not in opposite phase to the incident wave. Larger or 3D EUTS do behave better due to more variations of way length between radiator and antenna, and large receiving antennas have less problems then dipoles (especially active dipoles : small !!)./ Just a few notes to explain for the many differences that may happen between set up variations. Gert Gremmen -Original Message- From: owner-emc-p...@majordomo.ieee.org [mailto:owner-emc-p...@majordomo.ieee.org]On Behalf Of Alex McNeil Sent: dinsdag 20 augustus 2002 18:00 To: 'emc-p...@majordomo.ieee.org' Subject: Radiated Emissions setup Hi Forum, As we all know test setups are absolutely critical to EMC results. I have the good fortune of having a good pre-compliance radiated emissions site (3m OATS, Fully or Semi Anechoic Chamber). From using this site I see all sorts of "funnies" but still the most annoying is how much you can change the emission results just by changing cable positions. I carry out regular EMC audits and could never quite get the same results as 6 months previous, when that particular product was last tested (I keep the master product and was still getting different results due to setup). I now use an "Audit" board where I bundle the cables (30-40cm) in a particular "figure of 8" fashion via fixed wooden pegs. Thru' time I have convinced myself that this not only gives me worst case emissions but also that much sought after REPEATABILITY! I believe the setup is as per EN55022. I have a photograph* of this Audit board to allow this forum to comment on the good and the bad points of using such a system. Also, is there any reason I cannot take this Audit board to a Test House for Product Compliance testing and at the same time get correlation between a Compliance site and my own site? Photograph details (EUT with 3 X Serial Ports, PSTN and DC SELV power connection) 1. The 1M, 2M and 3M in
RE: Radiated Emissions setup
Only one comment: If you take this peg board to an OATS how can they maximize the cables? -Original Message- From: Alex McNeil [mailto:alex.mcn...@ingenicofortronic.com] Sent: Tuesday, August 20, 2002 10:00 AM To: 'emc-p...@majordomo.ieee.org' Subject: Radiated Emissions setup Hi Forum, As we all know test setups are absolutely critical to EMC results. I have the good fortune of having a good pre-compliance radiated emissions site (3m OATS, Fully or Semi Anechoic Chamber). From using this site I see all sorts of "funnies" but still the most annoying is how much you can change the emission results just by changing cable positions. I carry out regular EMC audits and could never quite get the same results as 6 months previous, when that particular product was last tested (I keep the master product and was still getting different results due to setup). I now use an "Audit" board where I bundle the cables (30-40cm) in a particular "figure of 8" fashion via fixed wooden pegs. Thru' time I have convinced myself that this not only gives me worst case emissions but also that much sought after REPEATABILITY! I believe the setup is as per EN55022. I have a photograph* of this Audit board to allow this forum to comment on the good and the bad points of using such a system. Also, is there any reason I cannot take this Audit board to a Test House for Product Compliance testing and at the same time get correlation between a Compliance site and my own site? Photograph details (EUT with 3 X Serial Ports, PSTN and DC SELV power connection) 1. The 1M, 2M and 3M indicate the Horizontal bundling of cables from RS232 ports which would go to a tabletop EUT peripheral (or leave open circuit). The 3 lengths are connected to similar ports. This covers the different lengths issues. 2. The P is the inline power supply O/P cable going to the EUT. This is bundled vertically as it represents the power supply sitting on a customers floor. 3. The T is the PSTN telecomms cable. Again bundled vertically as it represents the cable going from the EUT to the wall socket. Finally, I have never understood the EN55022 figure 10 note 1 "If cables which hang closer than 40cm to the horizontal ground plane cannot be shortened to appropriate length, the excess shall be folded back and forth forming a bundle 30cm to 40cm long". Does this mean you can cut the cable to 1m or ? even though you will be shipping say 2m cables with the product? *I have not attached the photograph, 212Kb. This will be sent to those requesting it i.e. to those people who are thinking of commenting on this email. I look forward with interest to this forums comments. Kind Regards Alex McNeil Principal Engineer Tel: +44 (0)131 479 8375 Fax: +44 (0)131 479 8321 email: alex.mcn...@ingenicofortronic.com --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list" --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list"
RE: Question on highest frequency used
I would guess the answer is b) 5x the 12GHz transmitter. I think (going from memory) ANSI C63.4 gives test instructions for receivers. The Local Oscillator or the receiver must be "active", i.e. receiving a real signal (alternately you can inject a test signal into the receiver). Thus making that a signal source at 12GHz. The 5x applies to the "highest frequency generated or used" by the device. Survey Says? Regard David Spencer Xerox Corp. -Original Message- From: Grasso, Charles [mailto:charles.gra...@echostar.com] Sent: Tuesday, August 20, 2002 12:23 PM To: 'emc-p...@majordomo.ieee.org' Subject: Question on highest frequency used Hi - and just when I thought I had it all figured out.. I have a question on the FCC requirement to test a product to the highest frequency used. Say a company has an RF receiver that has a DSP processor in it running at 50MHz. Lets also say that said receiver is pointed at a transmitter that has a 12Ghz signal. Should I test the receiver to a) 5X the 50MHz or b) 5x the 12GHz transmitter signal? We have an FCC interpretation - bet you can't guess what it is.. Charles Grasso Senior Compliance Engineer Echostar Technologies Corporation phone: 303.706.5467 FAX: 303.799.6222 Charles Grasso Senior Compliance Engineer Echostar Technologies Corporation phone: 303.706.5467 FAX: 303.799.6222 --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list" --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list"
RE: Radiated Emissions setup
Neil, I would like to see the pictures of your audit board. Without seeing the pictures I have the following comments. 1. I think this is a very good idea from a repeatability standpoint and I would like to consider adopting it. 2. It may be more trouble than simply draping the cables over the table edge, but less than bundling them properly. 3. Some of our customers bring their products in already attached to such a board with their cables all fastened securely in configurations accepted by their customers. This also lessens the setup time and gets them in and out quicker. 4. I believe that Note 1 of Figure 10 in EN 55022 refers to cables which connect one piece of gear on the table to another. If the cables were cut, it would require splicing or installing connectors. If a shorter cable were used, it may not represent actual use. I feel that generally customers having a two meter cable which is longer than needed would either drape it to the floor (which is not normally a metal ground plane), or bundle it neatly to keep it out of the way. On the other hand, since we as testers never know how equipment will be configured, the demand for repeatability requires that a system such as that described in Figure 10 be used. Robert Seay -Original Message- From: Alex McNeil [mailto:alex.mcn...@ingenicofortronic.com] Sent: Tuesday, August 20, 2002 12:00 PM To: 'emc-p...@majordomo.ieee.org' Subject:Radiated Emissions setup Hi Forum, As we all know test setups are absolutely critical to EMC results. I have the good fortune of having a good pre-compliance radiated emissions site (3m OATS, Fully or Semi Anechoic Chamber). From using this site I see all sorts of "funnies" but still the most annoying is how much you can change the emission results just by changing cable positions. I carry out regular EMC audits and could never quite get the same results as 6 months previous, when that particular product was last tested (I keep the master product and was still getting different results due to setup). I now use an "Audit" board where I bundle the cables (30-40cm) in a particular "figure of 8" fashion via fixed wooden pegs. Thru' time I have convinced myself that this not only gives me worst case emissions but also that much sought after REPEATABILITY! I believe the setup is as per EN55022. I have a photograph* of this Audit board to allow this forum to comment on the good and the bad points of using such a system. Also, is there any reason I cannot take this Audit board to a Test House for Product Compliance testing and at the same time get correlation between a Compliance site and my own site? Photograph details (EUT with 3 X Serial Ports, PSTN and DC SELV power connection) 1. The 1M, 2M and 3M indicate the Horizontal bundling of cables from RS232 ports which would go to a tabletop EUT peripheral (or leave open circuit). The 3 lengths are connected to similar ports. This covers the different lengths issues. 2. The P is the inline power supply O/P cable going to the EUT. This is bundled vertically as it represents the power supply sitting on a customers floor. 3. The T is the PSTN telecomms cable. Again bundled vertically as it represents the cable going from the EUT to the wall socket. Finally, I have never understood the EN55022 figure 10 note 1 "If cables which hang closer than 40cm to the horizontal ground plane cannot be shortened to appropriate length, the excess shall be folded back and forth forming a bundle 30cm to 40cm long". Does this mean you can cut the cable to 1m or ? even though you will be shipping say 2m cables with the product? *I have not attached the photograph, 212Kb. This will be sent to those requesting it i.e. to those people who are thinking of commenting on this email. I look forward with interest to this forums comments. Kind Regards Alex McNeil Principal Engineer Tel: +44 (0)131 479 8375 Fax: +44 (0)131 479 8321 email: alex.mcn...@ingenicofortronic.com --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list" --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscri
Re: EN 55022:1998 vs. ANSI C63.4
The idea of putting the ferrites on the cables is to prevent noise from outside the test site form entering the test site. My opinion is that you should not have to repeat the test as the ferrites do not have any effect on what is happening in the room where the test is being performed. Just one mans opinion. Steven - Original Message - From: To: Sent: Tuesday, August 20, 2002 9:16 AM Subject: EN 55022:1998 vs. ANSI C63.4 > > Probably won't get many responses this week as everyone with a travel > budget is now in Minnesota. However, I'll try it anyway. > > In the 1998 version of EN 55022, radiated emissions tests on table top > products are performed with a ferrite tube or clamp on each cable that > exits the test site (i.e. AC mains, telecom, I/O to remote control units). > ANSI C63.4 does not specify this. If I follow the EN 55022 procedure, is > it necessary to repeat without the ferrite clamps in order to satisfy the > ANSI test procedure? > > Thanks. > > Jim Hulbert > Pitney Bowes > > > --- > This message is from the IEEE EMC Society Product Safety > Technical Committee emc-pstc discussion list. > > Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ > > To cancel your subscription, send mail to: > majord...@ieee.org > with the single line: > unsubscribe emc-pstc > > For help, send mail to the list administrators: > Ron Pickard: emc-p...@hypercom.com > Dave Heald: davehe...@attbi.com > > For policy questions, send mail to: > Richard Nute: ri...@ieee.org > Jim Bacher: j.bac...@ieee.org > > All emc-pstc postings are archived and searchable on the web at: > http://ieeepstc.mindcruiser.com/ > Click on "browse" and then "emc-pstc mailing list" --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list"
Question on highest frequency used
Hi - and just when I thought I had it all figured out.. I have a question on the FCC requirement to test a product to the highest frequency used. Say a company has an RF receiver that has a DSP processor in it running at 50MHz. Lets also say that said receiver is pointed at a transmitter that has a 12Ghz signal. Should I test the receiver to a) 5X the 50MHz or b) 5x the 12GHz transmitter signal? We have an FCC interpretation - bet you can't guess what it is.. Charles Grasso Senior Compliance Engineer Echostar Technologies Corporation phone: 303.706.5467 FAX: 303.799.6222 Charles Grasso Senior Compliance Engineer Echostar Technologies Corporation phone: 303.706.5467 FAX: 303.799.6222 --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list"
Radiated Emissions setup
Hi Forum, As we all know test setups are absolutely critical to EMC results. I have the good fortune of having a good pre-compliance radiated emissions site (3m OATS, Fully or Semi Anechoic Chamber). From using this site I see all sorts of "funnies" but still the most annoying is how much you can change the emission results just by changing cable positions. I carry out regular EMC audits and could never quite get the same results as 6 months previous, when that particular product was last tested (I keep the master product and was still getting different results due to setup). I now use an "Audit" board where I bundle the cables (30-40cm) in a particular "figure of 8" fashion via fixed wooden pegs. Thru' time I have convinced myself that this not only gives me worst case emissions but also that much sought after REPEATABILITY! I believe the setup is as per EN55022. I have a photograph* of this Audit board to allow this forum to comment on the good and the bad points of using such a system. Also, is there any reason I cannot take this Audit board to a Test House for Product Compliance testing and at the same time get correlation between a Compliance site and my own site? Photograph details (EUT with 3 X Serial Ports, PSTN and DC SELV power connection) 1. The 1M, 2M and 3M indicate the Horizontal bundling of cables from RS232 ports which would go to a tabletop EUT peripheral (or leave open circuit). The 3 lengths are connected to similar ports. This covers the different lengths issues. 2. The P is the inline power supply O/P cable going to the EUT. This is bundled vertically as it represents the power supply sitting on a customers floor. 3. The T is the PSTN telecomms cable. Again bundled vertically as it represents the cable going from the EUT to the wall socket. Finally, I have never understood the EN55022 figure 10 note 1 "If cables which hang closer than 40cm to the horizontal ground plane cannot be shortened to appropriate length, the excess shall be folded back and forth forming a bundle 30cm to 40cm long". Does this mean you can cut the cable to 1m or ? even though you will be shipping say 2m cables with the product? *I have not attached the photograph, 212Kb. This will be sent to those requesting it i.e. to those people who are thinking of commenting on this email. I look forward with interest to this forums comments. Kind Regards Alex McNeil Principal Engineer Tel: +44 (0)131 479 8375 Fax: +44 (0)131 479 8321 email: alex.mcn...@ingenicofortronic.com --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list"
Re: Grounding in an operating room environment ...
Doug, You are really asking if the product is Type B (earthed applied part) or Type BF (isolated ground part) according the the classification of IEC 60601-1. The answer is that some types of medical equipment must be Type BF or even Type CF (direct cardiac contact) according to the appropriate particular standard, IEC 60601-2-X. For many types of equipment it is left to the manufacturer to decide. Generally speaking the longer and more invasive the contact with the patient, the more likely that Type BF or CF is required. In particular, in situations where many medical instruments may be connected to the patient simutaneously, e.g. in the operating room or intensive care, there is a greater need for isolated patient applied parts. This is to prevent a fault in one device causing dangerous leakage currents through the patient to earth via another device. Regards, Jon Griver http://www.601help.com The Medical Device Developer's Guide to IEC 60601-1 One final question - if some product which uses 115/230vac mains power and if there is to be metal contact between that product and a patient in an operating room environment, is it a matter of accepted practice that the mfr can decide the metal is grounded/ungrounded or must it be grounded as dictated by some standard? Regards, Doug McKean --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list" --- End of forwarded message --- --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list"
EN 55022:1998 vs. ANSI C63.4
Probably won't get many responses this week as everyone with a travel budget is now in Minnesota. However, I'll try it anyway. In the 1998 version of EN 55022, radiated emissions tests on table top products are performed with a ferrite tube or clamp on each cable that exits the test site (i.e. AC mains, telecom, I/O to remote control units). ANSI C63.4 does not specify this. If I follow the EN 55022 procedure, is it necessary to repeat without the ferrite clamps in order to satisfy the ANSI test procedure? Thanks. Jim Hulbert Pitney Bowes --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list"
