Startup currents are drawn for only a short period of time, when you
first turn the motor on. Unless the startup current trips some kind
of self-protect circuit, the steady-state number is the one you should
use for configuration planning. The power supply's rating will be a
continuous-duty rating. I suspect the steady state will be less than
1/3 of the startup, probably more like 1/10.
If it's a "wall wart" supply I wouldn't worry at all, they don't
usually have protection circuitry, they just depend on the transformer
winding resistance to limit the current to a level where they can
safely dissipate the heat generated (that is, even if you dead-short
them they shouldn't catch on fire...) That's why everything has a wall-
wart. If the wall-wart won't catch on fire even with a dead short,
the equipment doesn't have to get Underwriter's Lab approval, since
nothing that it does can trigger a fire hazard.
My guess is that things should work just fine. But you should be
aware of the outside chance of tripping a protect circuit.
On Dec 8, 2008, at 12:32 PM, Don Schmadel wrote:
I noticed that the power supply that comes with the Rosewill RCW-608
SATA/IDE USB adapter is rated at Output: DC +12V/1.5A. 1 to 2 Amps
appears to be typical.
On the other hand, the Seagate Barracuda 7200.11 SATA specs indicate
that the "Maximum start current, DC" is 2.8 Amps.
This is rather scanty information, and the vendors haven't responded
with any more. Does anyone know if this 2.8 A requirement will this
cause a problem?
-Don
