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Help finding an appropriate relay for a 12v 50amp power source!? Answered

I need to control a 12 volt 50 amp power source with a relay via arduino, and the relay that I am currently using isn't rated for such a high amperage. I'm fairly new to electronics, and would appreciate the help!

For reference, my current relay: songle srd-05vdc-sl-c



What 12V supply are you working with and what circuit are you using that will pull 50A?

If the power source can offer up to 50A but your circuit will only draw less than 10A. Then your current relay will handle the load just fine. Worry about what your circuit will draw not the max output of the power source. The circuit will only pull in what it needs.

Thank you for your reply! I was, fortunately, able to find an appropriate relay. I will still select you for best answer, though, for the assistance.

The 12V rails on many modern computer power supplies can handle upwards of 1500 watts (on the extreme end) and 750 watts on the 'enthusiast/gamer' end...A bit silly, but very possible on a small budget.

Individual 12V rails on PC power supplies can output as much as 30A and some go a bit higher but i have yet to see any PC PSU with a single 50A rated rail. Most PSUS keep the rails down around 20A since very few items in a PC require that kind of power. Things like Video cards that need that kind of power will require 2 power connectors from separate rails.

My power supply.

Single 12v rail, 62 amps. (multiple wires, connectors etc, but all +12 are connected internally).


The evga NEX1500 has 20 amps per rail that can run in parallel up to 124 amps total.


5 years ago

Here's my first find.
The second.

Have you considered a opto drive MOSFET ?


Look at automotive relays. They're usually the best compromise between rating and price.