I need some help. I want to be able to turn on an off a 24v source about 40 to 60 amps from an rc remote. Assume that the receiver will have constant power. All i need to be able to do is turn a separate power source on and off. I was looking at receiver controlled switches but I don't think they will supply enough amps. I'm sure someone has done this before. I'm just trying to find a good way to do it.

Thanks!!

Are you actually trying to turn the PSU off or are you looking to just interrupt the supply? Switching the PSU off shouldn't require much current. Interrupting the supply, you might need to put a high current relay in the circuit and use the receiver to control that.

Use an Rx switch and SPST relay.

^^^ use the BEC voltage and a relay that can handle the current. The switch energizes the relay which then allows the current to pass from your 24v source to where it's going. The 24v source could be used to energize the relay and the switch powered by the rx would turn that on/off. That much continuous current through anything other than 8 AWG is asking for trouble. Whatever path you choose make sure that it can handle that kind of power.

Also switching that current under load will murder the contacts on the relay.

try this if you require a switch..

They need something that works remotely, not a physical switch.

24v starter relay will work for one piece to this puzzle. Now just need the switch to energize it.

An appropriately designed RC switch should do the trick - just remember that the coil is going to need more volts than the receiver can supply, as was pointed out above, you should be able to feed it from the 24V supply. Back EMF needs to be managed too, or you could fry the RC switch.

A solid-state relay might be an alternative and there's likely ones that could be directly activated from the receiver.

Switching that kind of current is something to be careful about so, as gigaplex asked, does the 24V source have some way of controlling it? Many PSU's have control pins exactly for this purpose. For example, a standard ATX power supply only needs one pin to be grounded at low current for it to come to life.

Here is my project. I am working on a remote control Lawnmower. I am using the drive system off of a Wheel chair. I am using a smart drive duo to control the two motors for the drive system. This part will allow me to control it via a drone style controller. So, that is one stand alone system i plan on running on a 4s lipo. The lawnmower blade is a 24v system. I am going to run this on a 6s lipo. It would be nice to be able to turn the mower on and off while i drive it. If i can't get it to power it's self on and off i can always just leave it on, but it would be nice to shut if off to drive over a stick/hose whatever. Hopefully this paints a clearer picture.

Do you have any further details on the mower system? It almost certainly has an ESC integrated.

I'd use an ESC to power and control a brushless motor for the blade. Side benefit is the brake function can be used to stop the blade quicker, add a little safety margin. Seems like a lot of build and effort to use a brushed motor considering the power requirements, brushless needs a controller anyway. Potentially not much more expensive than a sufficient RC switch and relay setup, overall simpler.

How about a Power strip that runs off a wireless remote like fob that can be mounted to your transmitter lol. Where are you getting this 40amp 24v source.? Lead acid batteries? AC sourced power supply.?

Due note that 30-40 amps at 24vac is practically welding level power transmission.