Re: DC PSU for conducted immunity testing to EN61000-4-6
Why not build an unregulated linear power supply out of parts from Radio Shack? Or buy a cheap 12 Volt lead-acid battery 1 or 2 Amp trickle charger and put a filter cap on the output. As long as it is unregulated, it should not respond in any anomalous fashion to EMI. From: Chris Chileshe chris.chile...@ultronics.com Reply-To: Chris Chileshe chris.chile...@ultronics.com Date: Wed, 24 Sep 2003 09:33:29 +0100 To: emc-p...@majordomo.ieee.org emc-p...@majordomo.ieee.org Subject: DC PSU for conducted immunity testing to EN61000-4-6 Group, After quite a struggle to get a product through conducted immunity tests (clamp method), I finally discovered that the weak link in the chain was in fact my laboratory power supply which I have been taking along with me to a nearby test house. The problem remained undetected for a number of reasons, not least that I had used the same setup before at a different test house using their PSU ( Solartron ASxxx) and had better results, but mostly because we were using a small chamber dedicated to conducted immunity tests and using a camera to monitor the behaviour of the EUT behind closed doors and not keeping an eye on the PSU. When we eventually tracked the anomalous behaviour of the EUT to the PSU, we tried LISNs and a different PSU both of which improved the test results significantly but the outcome was still not good enough from a product compliance point of view. Question 1: Is anyone aware of a power supply suitable for this type of testing? The EUT draws a maximum of 30mA at 12VDC. I have been unable to find any Solartron PSUs on the web; probably long discontinued. Question 2: Has anyone tried to build a filter for this sort of thing and would this be the way to go? Best regards - Chris Chileshe - Ultronics Ltd - UK (O.O.O.) This e-mail has been scanned for all viruses by Star Internet. The service is powered by MessageLabs. For more information on a proactive anti-virus service working around the clock, around the globe, visit: http://www.star.net.uk --- 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: emc_p...@symbol.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc 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: emc_p...@symbol.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
Re: DC PSU for conducted immunity testing to EN61000-4-6
I read in !emc-pstc that Chris Chileshe chris.chile...@ultronics.com wrote (in 01c3827e.ebde2400.chris.chile...@ultronics.com) about 'DC PSU for conducted immunity testing to EN61000-4-6' on Wed, 24 Sep 2003: Question 1: Is anyone aware of a power supply suitable for this type of testing? The EUT draws a maximum of 30mA at 12VDC. I have been unable to find any Solartron PSUs on the web; probably long discontinued. I'm not surprised. The AS series had germanium transistors, I think. Question 2: Has anyone tried to build a filter for this sort of thing and would this be the way to go? What effect did the power supply have on the immunity? It's difficult to know with no data what a simple analog power supply would do. One would certainly need to know that in order to determine whether a filter was feasible and the optimum solution. -- 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: emc_p...@symbol.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
RE: DC PSU for conducted immunity testing to EN61000-4-6
Group After reading Ray's reply, I realise I had written LISN instead of CDN. Kindly replace LISN with CDN in my original posting. Rgds From: r...@rpgarner.freeserve.co.uk [SMTP:r...@rpgarner.freeserve.co.uk] Sent: Wednesday, September 24, 2003 1:39 PM To: Chris Chileshe; emc-p...@majordomo.ieee.org Subject:Re: DC PSU for conducted immunity testing to EN61000-4-6 Chris, I would suggest you need to change your test house. A good test house would already have power supplies available fed via filters to the test bench. They would also have ambient measurement information available to proof that their power supply was suitable for testing. I am also somewhat surprised that you make no reference to an ambient test having been performed on your set up. Also contrary to popular belief LISNs are not filters they only purpose is to provide a known impedance. I have in the past seen test houses cause more problems than they solve by not checking or using correct test set ups. Ray Garner EMC Consultant WRSL Message date : Sep 24 2003, 12:19 PM From : Chris Chileshe To : emc-p...@majordomo.ieee.org Copy to : Subject : DC PSU for conducted immunity testing to EN61000-4-6 Group, After quite a struggle to get a product through conducted immunity tests (clamp method), I finally discovered that the weak link in the chain was in fact my laboratory power supply which I have been taking along with me to a nearby test house. The problem remained undetected for a number of reasons, not least that I had used the same setup before at a different test house using their PSU ( Solartron ASxxx) and had better results, but mostly because we were using a small chamber dedicated to conducted immunity tests and using a camera to monitor the behaviour of the EUT behind closed doors and not keeping an eye on the PSU. When we eventually tracked the anomalous behaviour of the EUT to the PSU, we tried LISNs and a different PSU both of which improved the test results significantly but the outcome was still not good enough from a product compliance point of view. Question 1: Is anyone aware of a power supply suitable for this type of testing? The EUT draws a maximum of 30mA at 12VDC. I have been unable to find any Solartron PSUs on the web; probably long discontinued. Question 2: Has anyone tried to build a filter for this sort of thing and would this be the way to go? Best regards - Chris Chileshe - Ultronics Ltd - UK (O.O.O.) This e-mail has been scanned for all viruses by Star Internet. The service is powered by MessageLabs. For more information on a proactive anti-virus service working around the clock, around the globe, visit: http://www.star.net.uk 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: emc_p...@symbol.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc This e-mail has been scanned for all viruses by Star Internet. The service is powered by MessageLabs. For more information on a proactive anti-virus service working around the clock, around the globe, visit: http://www.star.net.uk File: ATT00011.htm This e-mail has been scanned for all viruses by Star Internet. The service is powered by MessageLabs. For more information on a proactive anti-virus service working around the clock, around the globe, visit: http://www.star.net.uk 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: emc_p...@symbol.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web
Re: DC PSU for conducted immunity testing to EN61000-4-6
Chris, I would suggest you need to change your test house. A good test house would already have power supplies available fed via filters to the test bench. They would also have ambient measurement information available to proof that their power supply was suitable for testing. I am also somewhat surprised that you make no reference to an ambient test having been performed on your set up. Also contrary to popular belief LISNs are not filters they only purpose is to provide a known impedance. I have in the past seen test houses cause more problems than they solve by not checking or using correct test set ups. Ray Garner EMC Consultant WRSL Message date : Sep 24 2003, 12:19 PM From : Chris Chileshe To : emc-p...@majordomo.ieee.org Copy to : Subject : DC PSU for conducted immunity testing to EN61000-4-6 Group, After quite a struggle to get a product through conducted immunity tests (clamp method), I finally discovered that the weak link in the chain was in fact my laboratory power supply which I have been taking along with me to a nearby test house. The problem remained undetected for a number of reasons, not least that I had used the same setup before at a different test house using their PSU ( Solartron ASxxx) and had better results, but mostly because we were using a small chamber dedicated to conducted immunity tests and using a camera to monitor the behaviour of the EUT behind closed doors and not keeping an eye on the PSU. When we eventually tracked the anomalous behaviour of the EUT to the PSU, we tried LISNs and a different PSU both of which improved the test results significantly but the outcome was still not good enough from a product compliance point of view. Question 1: Is anyone aware of a power supply suitable for this type of testing? The EUT draws a maximum of 30mA at 12VDC. I have been unable to find any Solartron PSUs on the web; probably long discontinued. Question 2: Has anyone tried to build a filter for this sort of thing and would this be the way to go? Best regards - Chris Chileshe - Ultronics Ltd - UK (O.O.O.) This e-mail has been scanned for all viruses by Star Internet. The service is powered by MessageLabs. For more information on a proactive anti-virus service working around the clock, around the globe, visit: http://www.star.net.uk --- 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: emc_p...@symbol.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
RE: DC PSU for conducted immunity testing to EN61000-4-6
Hi Chris, The power supply definitely should be decoupled by a standard CDN (f.a. CDN-T2) in order to couple the RF current from the calmp to ground. Then any standard power supply will probably do the job. This is exactly one of the major drawback (apart from needing higher power amps) that goes with the application of the EM-clamp. You might opt for CDN's for all cables to get better results on all tests. Note that the new EN 61000-4-6 allows for using only 2 CDN at a time. Regards, Gert Gremmen Approvals manager == ce-test, qualified testing Member of EMC committee CENELEC/IEC + Independent Consultancy Services + Compliance Testing and Design for CE + Improvement of product quality and reliability + Testing services according to: Electro magnetic Compatibility 89/336/EC Electrical Safety 73/23/EC Medical Devices 93/42/EC Radio Telecommunication Terminal equipment 99/5/EC Website: www.ce-test.nl Phone : +31 10 415 24 26 Fax :+31 10 415 49 53 == From: owner-emc-p...@majordomo.ieee.org [mailto:owner-emc-p...@majordomo.ieee.org]On Behalf Of Chris Chileshe Sent: Wednesday, September 24, 2003 10:33 AM To: emc-p...@majordomo.ieee.org Subject: DC PSU for conducted immunity testing to EN61000-4-6 Group, After quite a struggle to get a product through conducted immunity tests (clamp method), I finally discovered that the weak link in the chain was in fact my laboratory power supply which I have been taking along with me to a nearby test house. The problem remained undetected for a number of reasons, not least that I had used the same setup before at a different test house using their PSU ( Solartron ASxxx) and had better results, but mostly because we were using a small chamber dedicated to conducted immunity tests and using a camera to monitor the behaviour of the EUT behind closed doors and not keeping an eye on the PSU. When we eventually tracked the anomalous behaviour of the EUT to the PSU, we tried LISNs and a different PSU both of which improved the test results significantly but the outcome was still not good enough from a product compliance point of view. Question 1: Is anyone aware of a power supply suitable for this type of testing? The EUT draws a maximum of 30mA at 12VDC. I have been unable to find any Solartron PSUs on the web; probably long discontinued. Question 2: Has anyone tried to build a filter for this sort of thing and would this be the way to go? Best regards - Chris Chileshe - Ultronics Ltd - UK (O.O.O.) This e-mail has been scanned for all viruses by Star Internet. The service is powered by MessageLabs. For more information on a proactive anti-virus service working around the clock, around the globe, visit: http://www.star.net.uk 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: emc_p...@symbol.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc 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: emc_p...@symbol.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
DC PSU for conducted immunity testing to EN61000-4-6
Group, After quite a struggle to get a product through conducted immunity tests (clamp method), I finally discovered that the weak link in the chain was in fact my laboratory power supply which I have been taking along with me to a nearby test house. The problem remained undetected for a number of reasons, not least that I had used the same setup before at a different test house using their PSU ( Solartron ASxxx) and had better results, but mostly because we were using a small chamber dedicated to conducted immunity tests and using a camera to monitor the behaviour of the EUT behind closed doors and not keeping an eye on the PSU. When we eventually tracked the anomalous behaviour of the EUT to the PSU, we tried LISNs and a different PSU both of which improved the test results significantly but the outcome was still not good enough from a product compliance point of view. Question 1: Is anyone aware of a power supply suitable for this type of testing? The EUT draws a maximum of 30mA at 12VDC. I have been unable to find any Solartron PSUs on the web; probably long discontinued. Question 2: Has anyone tried to build a filter for this sort of thing and would this be the way to go? Best regards - Chris Chileshe - Ultronics Ltd - UK (O.O.O.) This e-mail has been scanned for all viruses by Star Internet. The service is powered by MessageLabs. For more information on a proactive anti-virus service working around the clock, around the globe, visit: http://www.star.net.uk 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: emc_p...@symbol.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
