I wanted a quick way to see the actual voltage of the batteries on my trailer and I wanted a way to easily connect my Viair Compressor to the trailer batteries. Here's a couple of pics of my idea. It works well for me.
To the left of the bracket, you see the quick disconnect/ protective cover sticking out from under the bracket. This simply unplugs so that I can plug the compressor in. In the middle is the momentary switch and then the volt meter.
Piece of scrap aluminum for the bracket
3 feet of both black and red #10 wire (for the compressor)
3 feet of both black and red #14 wire (for the volt meter)
Digital Volt Meter:
Momentary Push Button Switch:
2 Each Heavy Duty Battery Quick Disconnects:
Viair Portable Air Compressor:
NOTE: I ordered 2 of the battery quick disconnects. This allowed me to put a quick disconnect in the storage box, on the end of the compressor cable and another on the "battery clamps". This way, I can use the compressor connected to my trailer or I can connect the clamps to it and connect it to any 12 V battery.
The wiring is simple and straight forward.
NOTE: I have the 2 X 6 Volt Batteries so it is wiring is appropriate for these being wired in series to make 1 each 12 Volt Battery.
The the quick disconnect for the compressor is wired straight to the battery Positive and Negative terminals. The compressor has a fuse wired in line so I didn't need to fuse it.
The Volt Meter is wired directly to the batteries with the momentary switch wired into the positive wire.
All 3 pieces are mounted to the aluminum bracket which is then bolted to the aluminum cross member of the storage box.