I use a Yokogawa Type 3226 Universal Leakage Current Meter which is quite old, (10 years ++) and can measure ac current, dc current, and dc+ac current, with input resistances of 1, 1.5 and 2 kohms.
I also have a Simpson 229-2 (also quite old) which gives me very similar results to the above. The UL Data Sheets I use for the submission of results through the Client Test Data Program, (dated 1997) state "for measurements involving UL1950 second edition, use the Simpson 229-2 or equivalent. For UL1950 Third Edition testing, use the Simpson 228 or equivalent". A previous revision of these Data Sheets dated 1995 had the meter numbers the other way round, which might explain your problem. The 228 meter is the "latest" meter. UL (and CSA) seem quite happy to accept my results using the Yokogawa meter. I once got the UL engineer to bring his Simpson 228 with him, and if I recall correctly, it read slightly higher than the Yokogawa, and the UL engineer allowed me to continue using the Yokogawa. It would be interesting to directly compare results using the 2 Simpson meters on typical IT equipment. I suspect there would not be much difference in the readings. I do wonder how the Simpson 228 with a moving needle indication manages to meet the 1 MHz frequency requirement of IEC 60950. I have literature on a HIOKI 3155-01 Leak Current HiTESTER, which can be fitted with networks for 990/1010-1/950, or for IEC 601-1. IT IS EXPENSIVE (2110 pounds + 245 pounds for the 950/990 network). I thought about getting this meter, but as long as UL and CSA accept the results from my "golden oldie", I couldn't justify it !! John Crabb, Development Excellence (Product Safety) , NCR Financial Solutions Group Ltd., Kingsway West, Dundee, Scotland. DD2 3XX E-Mail :[email protected] Tel: +44 (0)1382-592289 (direct ). Fax +44 (0)1382-622243. VoicePlus 6-341-2289. > -----Original Message----- > From: Scott Douglas [SMTP:[email protected]] > Sent: 29 November 1999 13:31 > To: [email protected]; [email protected] > Cc: [email protected] > Subject: RE: Earth Leakage Measurement Circuit per EN 60950 > > > Peter, > > I own and once used a Simpson 228 and was told that it did not comply with > the test requirements of '950. So I bought the Simpson 229-2 and that was > accepted. Since then, the standard was changed again and the 229-2 was no > longer compliant. I ended up buying an ED&D LT-951 Leakage Current Tester > that has since been accepted as performing the test according to the > standard. I never really understood the total issue (did not spend the > time > to) and just bought equipment that would satisfy those agency guys. Shame > on > me. > > I would like to hear from others as to what equipment they use and does > anybody really know if it complies to the standard? > > Scott > [email protected] > ECRM Incorporated > Tewksbury, MA USA > --------- 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).
