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Franc Zabkar Franc Zabkar is offline
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Default switcher dummy loads

On Thu, 01 Apr 2010 21:36:28 -0500, bob urz put
finger to keyboard and composed:

I am working on a switching power supply from an older Avid hard disk
array. The array itself has proprietary Ultra SCSI drives in it.
No documentation is available.

The power supply seems to have issues and blew the fuse. nothing seems
to be shorted and no caps are bulging. As far as i can tell, the PS is
about 12volts at 15 amps and 5 volts at 12 amps or so. I was thinking of
hot wiring the supply outside of the unit and thought best to load down
the rails some. So, what would be an acceptable dummy load(s) for a
supply of that ratings? would a couple of amps per rail load sufficient
to start up and maintain regulation?

I am going to solder it up, i i have found no smoking guns so far.

bob


FWIW, I have a minicomputer PSU that delivers 150A @ 5V. Whenever a
chassis was unloaded, the PSU was loaded with a fan cooled, 1 ohm, 50W
aluminium clad resistor.

- Franc Zabkar
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