Home // Electronics // So you need a cheap 40 Amp 12V supply?

So you need a cheap 40 Amp 12V supply?

Coming up this summer I will be building a 3D printer. Did you know that they draw a little bit of juice? Well just so happens that I had a Dell Power Edge 2650 laying in the basement of my house. Now you may not have one but you can get the power supplies off of E-Bay for roughly $10.


These power supplies can be used for a number of things to include Ham radio, 3D Printer power supplies, and starting fires. (Please realize electricity is inherently dangerous.) Ultimately if you were to try and buy a pre-built switching power supply with this kind of amperage you will pay well over $100 from most electronics shops.

This is the exact make and model of the one I am using just so we are clear.



This is a diagram of how I wired this particular power supply. (Please realize electricity is inherently dangerous.) Again, use caution!



These are the readings that I pulled off of the power supply. You can see the voltage and polarity that I detected.



The 5V portion of the circuit is provided through the small pins. If you test the pins in the top left you will find your 5V line (pin 1 -3 left to right).

Ultimately this is a great 12V switching power supply. It can be used for radios and whatever other electronics you may have in the house. The 5V portion isn’t really that impressive but who cares when you have 41 Amps of 12V to use.

Fecke – KJ4ZRZ

One last time!

(Please realize electricity is inherently dangerous.)

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