I just spent the last four days under my trailer installing jacks and conduit. The jacks are UltraFab PowerTwin II electric stabilizing jacks. They aren't cheap but this is a big part of the quick setup/takedown concept I am building.
First, I got rid of the factory wiring and breakaway battery with those poor connectors.
My breakaway circuit will run directly off the main battery. Actually, I may not use breakaway at all. Is it really necessary? Notice the tongue jack has been removed (not easy since it was welded on). The front jacks can easily lift the tongue.
Rear jacks are retracted here. Front jacks are laying on the ground. I drilled holes in frame I beam and jacks. If the frame rails were even with the outside edge of the trailer, I think it would be a lot more difficult and steel mounting cross members would have to be welded in. Since I have narrowed axles, the frame rails are set in by 12".
This is the relay array for the control of the jacks. Each jack has an up and down relay so there are eight total. The tow vehicle harness goes to the terminal strip with all the yellow wires. From here I rewired all the lights and brakes. There is a relay here that takes over the brakes and backup lights and provides full power to them. This is activated by the "master jack switch". So when I go into setup/takedown the brakes will be locked for additional safety. When the master is switched off, the no power will go to the jacks so they can't accidentally short out and deploy while driving.
The master jack switch will be installed on the tongue under the generator box cover. There will be four momentary up/down switches, one for each jack. Ultrafab makes a radio controlled relay box that does the same thing but I wanted to build my own with upgraded power components like 40A relays and 8ga wires. There is a 100A master solenoid and independent fuses on everything.
Conduit and holes - not fun to install
Brake wires are 10ga in conduit. They split off from the center so left and right sides are electrically balanced. I wired the front and then rear, so front may get a little more power than rear. I hope thats not a mistake.
The jacks can lift my trailer no problem. The lifting power is not even - the further they extend, the more leverage they get, and the more power they deliver. I haven't tried to lift both wheels off the ground on the same side. That might not be good for the motors even if they could do it.
Overall, I am pleased with the quality of the Ultrafab PowerTwin II jacks. They are thick heavy steel and even if the trailer is too heavy to lift, they would be worthwhile for stabilizing. I did have to cut a bit off the corner of the legs because it interfered with the motor mounting bolts. It was either that or cut off the bolts by 1/4". I decided to use a nylon lock nut and take advantage of that extra length. It is kind of hard to imagine how Ultrafab let this slip through since it clearly couldn't work as shipped.
