We want to use a Smittybilt 2781 to quickly fill our tanks on our T-shirt cannon bot, is there any way we could wire this compressor to work on the standard control system? It doesn’t have to be legal. If it’s too much current draw for the PCM Compressor Out, maybe we could wire it to a motor controller and a 40a PDP Wago slot, if that would work. Thanks.
I’d recommend using the pre-RoboRIO way and wiring it to a spike. You might be able to use a motor controller, but if you have a spike laying around, it’d be less overkill/more supported
Since this is not for competition, you should look for a 12V relay that can handle the current (most likely mechanical, but there may be solid state options as well). DigiKey is a good place to shop. If you can find one with a coil voltage of 6V you may be able to drive it directly from the relay outputs on the Rio, but if you find one with 12V coils you could do a staged relay (e.g. a solid state relay driving the 12V coil of the larger mechanical relay). Then you can do the compressor control in software rather than using the PCM, or if you find one with a 12V coil, even use the PCM to drive the larger relay.
I have seen automotive relays up to 75A. Couple that with a 50A MAXI or bolt-in inline fuse and some 10AWG copper wire (unless the run is quite long), you should be good to go.
I would use the PCM compressor output to switch a relay which powers the compressor. I would power that relay though a 40A breaker channel. I’m a big fan of these guys, which also come in 60/80A flavors.