High Current Switch Solution for Hobbiest

[babyd3k]

Hobbiest here trying to make a rotary switching system to switch between a 1000w DC power supply and an external DC supply of the same input plus an all turned off position. The first power supply is running at 12 vDC and the 2nd input could be anything from 8-36 vDC. I can find rotary switches that have the positions and layouts I want but nothing that can handle the loads I would put the switch under.

I guess my question is what would a real engineer do, I was thinking of putting a solenoid in but I don't have any experience with then so before I bit off more then I could chew I thought I'd come ask the experts.

Thanks in advance.

 

[Fish4Fun]

babyd3k,

Welcome to PF!

1000W @ 12Vdc is 83A! Switching 83A is a non-trivial feat! 83A is in the welding range of currents, and needs special attention. There are relays capable of handling these kinds of currents, but they are expensive, very expensive. There are semiconductors capable of handling this amount of current, but the design criteria are difficult at best. I would seriously consider finding a solution that does not involve switching 83A under load. If you are simply interested in switching between power supplies when they are NOT under load the problem becomes much easier. A simple double pole double throw knife switch will do the job.

Fish