Re: SMPS Derating reqs for Altitude range of 5000-10000ft

Actually, it is both. The decreasing density of air results in a lower voltage withstand and a lower rate of convection cooling.. IEC 60950 only addresses the safety aspect of the change, not the operational aspects. acar...@uk.xyratex.com (Andrew Carson)@majordomo.ieee.org on 01/04/2002

Re: Mains fusing

Kyle, In UL 60950, Sec. 3.4.6 there is a requirement that all hot lines be switched off simultaneously. If you are powering your equipment with 240 VAC then in the US there are two hots and a neutral. 120 VAC line to neutral and 240 VAC line to line. Hence the UL requirement for a two pole

Re: Capacitor Discharge Test

cc: (bcc: Ed Rauch/MAIN/MC1

Re: NEC

. This normally satisfies the AHJ. wo...@sensormatic.com on 09/26/2000 08:02:58 AM Please respond to wo...@sensormatic.com To: emc-p...@majordomo.ieee.org cc:(bcc: Ed Rauch/MAIN/MC1) Subject: NEC This question is in regard to Class 2 and 3 circuits according to the US National Electrical Code

Re: Battery Safety

I've seen this resistor used for the low battery alarm circuit. It keeps the battery voltage from rising as load is shed and confusing the low battery alarm circuit. There is no safety reason that I know of. 91K ohm is an odd value though, left overs from another product? I'm assuming that the

Hacking of RCIC

Article in Tech News about the hacker. http://technews.netscape.com/news/0-1005-200-2722466.html?tag=st.ne.1002.tgif.ni Apparently he hacked many sites to spread his message. --- This message is from the IEEE EMC Society Product Safety Technical

Re: Correction factor for power supply cords.

for the safety of equipment. If you are using a flexible cord in a high ambient I would contact the mfg for the appropriate derating. Kelly Tsudama ktsud...@cisco.com on 03/09/2000 09:33:14 PM Please respond to Kelly Tsudama ktsud...@cisco.com To: emc-p...@majordomo.ieee.org cc:(bcc: Ed Rauch