Question about 12V DC power supplies

Old 06-26-14, 01:46 PM
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Question about 12V DC power supplies

It has been so long since I studied basic electricity that I cannot remember some of the most basic info. Perhaps someone here could assist. Can you safely use a 12 volt power supply rated at 30 amps to power a 12 volt 5 amp device? Does the 5 amp device only use 5 amps of the available power or will using a 30 amp power supply fry the 5 amp device?
Thanks for your help
Old 06-26-14, 02:17 PM
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Welcome to the forums.

You can use a larger current power supply to run a lower current item. It would be a good idea to fuse the line to the device at the maximum supply size that should be used.

So use an inline 5A fuse and you should be all set.

I work on a lot of mobile equipment and have a 13.8vdc @ 90amps power supply feeding my bench. I have a bank of circuit breakers that I can switch inline to protect the device I'm working on.

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