Surge suppressors

Marshall E. Fryman mfryman at
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,

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