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Adding Bigger relay to RC relay board

hello, I was interested in your RC relay board kit Pololu RC Switch with Relay (Partial Kit)
and wondered if it was possible to solder in a higher amp relay? Looking to upgrade to at least a 20A relay.

Could I wire in one of these in place of the 10A relay that comes in the kit?


Or would it make more sense to use one of the RC switches (Pololu RC Switch with Digital Output) with a higher amp relay module like this one: https://www.amazon.com/Yeeco-Current-Normally-Electric-Transfer/dp/B00R7TTSMI/ref=sr_1_3?crid=1YPVLN4UPWQTE&dchild=1&keywords=20a+relay+module&qid=1612224095&sprefix=20A+relay%2Caps%2C219&sr=8-3

I guess if I did this I would need to also include a 5V regulator right? Maybe something like a 7805? I basically want to control a 12v 20A relay with an RC signal coming off a receiver that is powered by 7.4v. So Iā€™d need to step down the 7.4v from the receiver to supply the 5v logic power for the RC switch correct?


Thank you for your interest in our RC switches. The relay you link to does not have the same form factor as the sugar cube relay on the RC switch with relay so it might be challenging to wire it. Instead, I recommend using our Pololu RC Switch with Small Low-Side MOSFET with your 20A relay.

This board requires a 2.5ā€“5.5 V power source supplied to VCC, so you will need to step-down the 7.4V battery voltage. A 7805 would work, but you might consider using a more efficient step-down switching regulator.

Alternatively, you might consider our Pololu RC Switch with Medium Low-Side MOSFET as it has a on-board regulator that allows it to be powered between 2.5-16V, though the MOSFET would be slightly overkill for actuating the relay.

Also, you will probably want to add a flyback diode in parallel with your relay.

ā€“ Jeremy