I have all the Ray Allen parts on my RV8, and an Infinity grip. I simply used the trigger grip to switch the power supply to the trim circuits, and the coolie hat switches grounds to the relays. I have to hold the trigger in, then select the coolie hat for direction and axis. If a relay sticks closed, I will end up a little out of trim, but no runaway is possible, much like the certified setup. This system has worked well for almost 6 years now.

 

If your enable switches ground just like the coolie hat on most installations, you have no protection from a stuck relay except to be really fast pulling a breaker (unlikely I think).

 

John Huft

RV spy