mark@intek01.uucp (Mark McWiggins) (01/03/91)
We recently had some power supplies fried by a Unison Unipower 600. We had too much of a load plugged into the circuit the UPS was plugged into, and instead of doing anything protective or rational like shutting itself down, it burned up the power supply on a PC and a modem (at least; other negative results are possible). I've heard good things about some Unisons, but apparently this one wasn't one of those. Unison is aware of the problem, but I don't know about any upgrade/swap policy. -- Mark McWiggins Integration Technologies, Inc. (Intek) +1 206 455 9935 DISCLAIMER: I could be wrong ... 1400 112th Ave SE #202 Bellevue WA 98004 mark@intek.com Ask me about C++!
rcd@ico.isc.com (Dick Dunn) (01/04/91)
mark@intek01.uucp (Mark McWiggins) writes: > We recently had some power supplies fried by a Unison Unipower 600. > We had too much of a load plugged into the circuit the UPS was plugged > into, and instead of doing anything protective or rational like shutting > itself down, it burned up the power supply on a PC and a modem ... Can you tell anything about the failure mode? What did the UPS do that caused the power supplies to fail? It seems unlikely that an overload on a UPS would cause an overvoltage on the output. I've been trying to postulate some other sort of failure (in which the nature of the power supply on the attached device would play some part) - such as clipping in the UPS output turning into garbage in the power supply. Is this UPS a sine-wave output type? > ...Unison is aware of the problem, but I don't know about any > upgrade/swap policy. Do they say anything about what to do to avoid it (other than the obvious "don't overload the UPS":-), or what types of devices would be susceptible? Is there a danger of damaging components beyond the power supplies in the attached devices? -- Dick Dunn rcd@ico.isc.com -or- ico!rcd Boulder, CO (303)449-2870 ...Mr. Natural says, "Use the right tool for the job."