Richard, This was our intuitive thought too. However, I do not fully understand the discharge network and do not know, for instance, if the total joules delivered to the coupler is independent of load or impedance. Does the network always fully discharge?
Today we spent some time to capture it. The following test was run on the AC: One EUT was connected to the coupling/decoupling network. A digital scope and fast Fluke probe was used to capture the voltage waveform at the input of the EUT. The data was plotted. A second EUT was added in parallel to the coupling/decoupling network. The test was re-run (no moving the probe) and the data was plotted. To my surprise, there was no change in waveform. My expectation was to see no change in rise time but to see a much faster decay time. A second test was attempted with a Fischer F-33-1 current probe. Not successful. The subject EUTs pull approx. 1/4 Amp, no surge protection devices. The test equipment is Keytek ECAT system (E4551 and E501A). We are proceeding to make a justification of the method (for these particular EUTs ONLY) that the individual EUTs are not under-stressed. I would like to seek additional input from the group. Unfortunately, most senior staff at Keytek involved in the development of the system have left. If anyone knows of whereabouts, please email. Also if anyone has a contact at Schaffner or Haefely. Best Regards, Dale Albright -----Original Message----- From: [email protected] [mailto:[email protected]] Sent: Wednesday, May 03, 2000 12:11 PM To: [email protected] Subject: RE: Surge I assume that you mean applying the surge energy to multiple power ports (or I/O ports). Consider the energy produced by the surge generator and how that energy is dissipated in the EUTs. If there is one and only one port being tested, would not the energy being delivered to that port be much higher than if multiple ports were being tested at the same time? I think the answer to your question is that you cannot test multiple ports since each of those ports would be under-stressed. Richard Woods ---------- From: Dale Albright [SMTP:[email protected]] Sent: Wednesday, May 03, 2000 11:14 AM To: [email protected] Subject: Surge Group, A question came up today regarding testing multiple EUTs for surge (61000-4-5). I spoke with the secretary of the subcommittee 77B (Jacques Delaballe) on this subject. We agree that: The method is not part of the standard; If the results are positive (EUT passes) then maybe OK; If EUT fails, then indeterminate. What are your thoughts? Regards, Dale Albright ------------------------------------------- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: [email protected] with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: [email protected] Michael Garretson: [email protected] For policy questions, send mail to: Richard Nute: [email protected] ------------------------------------------- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: [email protected] with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: [email protected] Michael Garretson: [email protected] For policy questions, send mail to: Richard Nute: [email protected] ------------------------------------------- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: [email protected] with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: [email protected] Michael Garretson: [email protected] For policy questions, send mail to: Richard Nute: [email protected]
