The receiver is powered by an external 12 volt system. The relays power the circuit (check current rating). I used the battery on the generator for that purpose. My Generator has a push button start (Normally Open circuit) so it was fairly easy to wire up. I only have a toggle switch for the on off switch (I leave it on all the time). They have a impressive range also, It works up to 600 feet away.
My original reason for purchasing this was for an electric gate I am installing but had to experiment with it first.
Here is another transmitter/Receiver combo that may meet all your needs. There is a wiring diagram with the below link.
http://cgi.ebay.com/RF-Wireless-Remote-C...1742.m153.l1262
