answering 6/18 posting from [EMAIL PROTECTED] (Tom Brinkman)
Tom,
You are correct that the UPS has surge/spike protection within it (at
least all of them that I've run across). And, I've found that the
surge/spike protection built in to the UPS rivals the best separate units
available [I had a data corruption problem where surge/spike effectiveness
was obvious] -- remember that I bought good surge/spikes and UPSs, your
mileage may vary. None-the-less I've always used a surge/spike before my UPS
and (later on) a surge/spike/RFI after.
I replaced my UPS with a new APC 650VA earlier this year. I don't
remember reading anything saying not to also use surge/spikes inline [though
you are correct that it would not strictly be needed], but remember that I
volunteered to being paranoid about this. I've had data problems caused by
powerline irregularities and fixed them with surge/spike and UPS additions.
[I also recommended a surge/spike & UPS combination to one of my customers
when I was a technician and had that customer's problems were cut over 90%.
I guess nothing is 100%.]
Even if APC did recommend use of no other in-line surge/spike units,
unless there was a VERY good reason for not doing it, I would run extra
surge/spikes anyway. Better surge/spike units use better components and will
stand up to more line abuse before beginning to deteriorate, but the problem
remains: ALL surge/spikes deteriorate with exposure to powerline
overvoltages that are in their working range, and there is no way to tell
this without laboratory instrumentation. With cheap surge/spike units
combined with bad line conditions it might be wise to replace the unit every
six months. Normally you do not replace one at all unless it took a serious
"hit" [you can usually test if it is dead, it will be shorted]. If
something's going to have to be replaced early I'd rather it was $50 to $100
for a surge/spike, not $300+ for a UPS. I put the newest & best surge/spike
nearest to the computer, and the oldest next to the power line. In this
configuration my APC has automatically handled low line voltage conditions
and momentary outages easily. In Windows, where I have UPS monitoring
software, everything is reported & metered just as it should be.
-Gary-
