Adding additional relays to 202U

I am working on a project using 202U to control a 4 wire, 1 phase, 3/4 HP 120V AC motor in forward and reverse to raise and lower a boat lift remotely. I believe I can do it if I add two more relays to work in tandem with relays 1 and 2. I have read that it is possible to add two relays and power them with onboard the 5v port, but cannot find any documentation on specifically how to do this.

Does anyone have suggestions on:

  1. How to expand the 202U to 4 relays so that relays 1 & 3 operate together and relays 2 & 4 operate together
  2. Have easier ideas on how to control forward and reverse of a 4 wire AC motor using only 2 relays?

Phase one is to get it working using momentary on-off. Phase two will integrate latching mode & limit switches to stop the lift automatically at the top or bottom of travel.

Thanks so much for your thoughts!

To clarify- the existing lift control “drum switch” has the four wires coming from the motor and the black “line” and white “neutral” wires coming from the 120v mains. Six wires total connected inside the existing up/down switch.

Switch wiring diagram:,w_800/v1490099742/drum_wiring_rsxwby.jpg

Hi Richard,

Sorry but my knowledge on the AC motor forward & reverse is very limited,

— One of our customer is using contactors to control lift motors.

I just remember one of our customer use our (customized) 2 relays receiver to control lift up/down, and he is using our relays to control contactors, then use contactors to control the motor (not directly relay->motor).

Because our onboard relay, when used with inductive load like motors, the rating is only 6A @ 14Vdc, using it exceeding rating will cause our relay meltdown very quickly.

For more details about why use contactors, please see

— About 202U expand relays.

Sorry it is not possible with 202U, the relay expansion port is for 402U receiver, and I’m afraid it is not to expand big relays for motors…

— Other info on AC motor reverse

I did a quick search on Google,

Maybe you can ask there about motor reversing? stackexchange is a very popular place where you can get answers very quickly.

Thanks and let me know if you have other questions.

THANK YOU! I had pretty much decided to use the 202U to control a bank of high current relays and your comments have convinced me to try it. Thanks!