Surge suppressors
Marshall E. Fryman
mfryman at futuraintl.com
Fri Oct 25 10:42:32 PDT 2002
Go to Radio Shack and pickup a meter that will tell you how many amps the
units draw (about $70). I've got several 2U boxes that pull pretty close to
2.5 amps each (dual CPU, dual drive, but otherwise similar to what you
described) using one of these meters. The strange thing was that my 4U
units (dual CPU, 5 drives) only pull 2 amps. After asking around a bit, we
discovered that the 4U box uses 110V AC fans and the 2U uses 12V DC fans.
According to an electrical engineer that works with us, 12V DC fans play
hell with a switching power supply.
At any rate, we got APC surge strips rated at 15A and run 5 units per strip
to give us a bit of a safety margin. We plug the UPS's into the strips and
then the racks into the UPS's. Multiple individual UPS's turned out to be a
lot cheaper than one big unit. Makes for a lot of weight on the rack, but
cost was the primary concern. We also ran into the same problem you did
with the carpet, so far our solution is to get four guys together to move
the rack. :)
Hope it helps,
Marshall
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