I agree that you should test and progressively increase the levels, because the lower level tests pre-condition the samples and if you fail then you have already obtained the data to apply the highest passing level. This is even more important when you are doing more destructive tests like TOV.
Monty Griffith Senior Product Safety Engineer EMC Quality Manager Intergraph Compliance Services Ph. (256) 730-6017 Fx. (256) 730-6239 http://cscsrv.ics.ingr.com -----Original Message----- From: Lyons, Jim [mailto:[email protected]] Sent: Thursday, August 19, 1999 1:49 PM To: 'Jim Hulbert'; [email protected] Subject: RE: EN50082-1:1997 & EN55024 We also fully test at each lower level up to the one we need to pass. It is time consuming, but that is what the standards call for, and that is what we do. I don't want to have to explain to some AHJ some day why I didn't follow the test procedure. Typically, we test our equipment, in-house, to one level higher than that required for the CE Marking. I have also noticed a test lab taking some shortcuts by cutting down on the number of hits/surges at the lower levels, and then doing the recommended number at the top level. Jim Lyons Mgr - product Compliance GTECH Corp. -----Original Message----- From: Jim Hulbert [mailto:[email protected]] Sent: Thursday, August 19, 1999 10:07 AM To: [email protected] Subject: EN50082-1:1997 & EN55024 Immunity test standards EN50082-1:1997 and EN 55024 call out the basic standards EN61000-4-2 and EN61000-4-5 for ESD and Surge. EN61000-4-2, Section 5 starts out "The preferential range of test levels for the ESD test is given in table 1. Testing shall also be satisfied at the lower levels given in table 1." EN61000-4-5, Section 5 contains similar wording. This is how we perform our compliance tests. We start at the lowest test voltage levels from the respective tables and step up to the test levels called out in EN50082-1/ EN55024 (or higher, depending on our own in-house product spec.) However, I have noticed that some test labs go straight to the levels called out in EN 50082-1/EN55024 and skip testing at the lower levels. I believe this approach is incorrect because it does not conform to the requirements of the basic standard and is simply not a complete test. As explained in EN61000-4-5, the non-linear current-voltage characteristics of the equipment under test should be considered and the test voltage should therefore be increased by steps up to the test level specified in the product standard or test plan. The same rationale applies to ESD testing where current-voltage characteristics are also non-linear. How do others approach these tests? Are we adding unnecessary test time by starting at lower test voltages and stepping our way up or are the test labs that go straight to the maximum test levels overlooking an important aspect of the testing? Jim Hulbert Senior Engineer-EMC Pitney Bowes --------- This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to [email protected] with the single line: "unsubscribe emc-pstc" (without the quotes). For help, send mail to [email protected], [email protected], [email protected], or [email protected] (the list administrators). --------- This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to [email protected] with the single line: "unsubscribe emc-pstc" (without the quotes). For help, send mail to [email protected], [email protected], [email protected], or [email protected] (the list administrators). --------- This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to [email protected] with the single line: "unsubscribe emc-pstc" (without the quotes). For help, send mail to [email protected], [email protected], [email protected], or [email protected] (the list administrators).
