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Powering a 12v DC fridge ? Answered

Hi, I have a 12VDC fridge and am trying to convert a computer power box to supply power to it.
I started with a ATX type and have problems with it resetting itself after the compressor restarts itself after reaching temp. I have a 10Watt resistor connected to the 5V wiring to keep it running during full temp switch off, but when frigde restarts itself the power supply resets.

I am now trying a AT 230W box and it does not reset but under load I only get 10.4v, not enough to operate fridge for cooling.
Any sugestions how to lift voltage as when connected to motherboard and 4 hdd's it generates 12v.

Sorry I should add that the fridge is 12v 4.2amp and the power box is 12v 8amp. I have tied 2 x AT type boxes with same result.
Thanks Tim




7 years ago

if its a pump operated one it wont work as Re-design said but if it is a peltiair one it should work as its just a chip i know i have a small one that can stor like 9 cans of soda and it came with a 5 amp adapter 50 watts i got it for a dollar at a garage sale. i cut off the connector halfway and now i can use it in my car with a adapter!!


8 years ago

Stall current is much larger than quiescent.

one method for determining the stall current required for your application is outlined here http://combots.net/wiki/index.php/Stall_current


8 years ago

When the compressor starts up it draws a lot more power than when running.  Computer power supplies probably don't do well in a surge situation.  I would think that's your problem.

Can you find out what the surge is on compressor startup?