I bought a 410 amp power inverter yesterday so I could charge my laptop without starting the generator. But the 12V receptacle above the dinette (for TV use only, it says) didn't work. Evidently the wires are too small going to that 12V outlet, causing power loss. My inverter would stop after being plugged in for only a minute, giving a low voltage warning.
The inverter showed 10.9 volts when it shut off, but the battery was still reading 12.6 volts at the time. Undersized wiring was the culprit.
Not to be beaten, I checked the Progressive Dynamics power control center, looking for a way to get 12 volts from it. There were two unused fused 30 amp circuits left on the power supply. Even though my inverter pulls 41 amps at full load, I don't plan on ever using it to that extent, so I decided a 30 amp circuit would suffice. And anyway, if the inverter pulls over 30 amps the fuse will blow, so it's safe. It won't hurt the inverter.
Part I used were:
-1 panel mount 12 volt receptacle with spade connectors for connecting the DC electricity (bought from a boating supply store, about $8)
-Two 3 foot lengths of 10 gauge multi-strand wire (about $3 total- at Lowes)
-A small package of spade connectors, male and female ($3- at Lowes)
-One 30 amp auto fuse (had it in my spares)
-Flat and phillips screwdrivers
-Electric drill and a 3/16 drill bit
-Wire terminal crimpers
-Wood chisel (only because I mis-positioned the receptacle hole through the panel, and had to remove some of the support plywood in order to fit the mounting nut on the threaded body of the receptacle)
I'm not recommending you do this yourself. I'm just describing a modification I made to my TT. (Disclaimer- If you try this on your own, don't blame me if you blow up your power controller, or start a fire and burn down your trailer, or electrocute yourself. I'm not liable for any mistakes that may be in these instructions, or any mistakes you might make. To be on the safe side, have a licensed electrician do this for you. End- Disclaimer
How I did it:
-Removed the under-refrigerator drawer to gain access to the back side of the power controller
-Use the mounting nut (taken from the body of the receptacle) as a guide to mark the size of the hole I needed to cut out. I just positioned the nut where I thought it should be and use the inside of the nut as a guide to draw a circle on the panel, next to the power controller. I should have marked the hole a half-inch farther away from the panel to give room for the nut. As it was, there was a strip of plywood (used to support the power controller) in the way.
-Drilled holes all the way around the marked circle, then used the side of the drill bit to finish cutting out the circle.
-Used the chisel to remove enough plywood so there was room for the nut to tighten on the back portion of the receptacle body. Again, if the hole was positioned correctly, this wouldn't need to be done.
-Slid the receptacle into the hole and tightened the nut on the back.
-Made sure the receptacle was positioned squarely, then screwed in the mounting screws, one on each side of the receptacle front.
Here's what I did with the wiring.
-Disconnect the negative wire from the battery!
-Strip about 3/8 inch of insulation from each end of the two wires
-Crimp on a female connector to one end of the white wire.
-Attach the other end to the negative terminal block, screwed to the floor. There were no open spaces in the terminal block, so I doubled up two of the smaller wires in one connector to free up a connector for the new wire.
-Crimp a male terminal on one end of the black wire, and a female terminal end on the other end
-Find the black wire coming out of the power controller labeled with the number "1". It should be unconnected to any other wires, with a crimp connector on its end.
-Cut the wire close to the connector on the end of wire #1, and strip off 3/8 inch of insulation
-Crimp on a female terminal end
-Connect the male terminal on the end of your 3 foot black wire to the female connector of wire #1
-Connect the female terminal end of the 3 foot black wire to the middle spade on the back of the receptacle
-Connect the female terminal on the end of the 3 foot white wire to the other spade at the back of the receptacle.
-Insert the 30 amp fuse into the #1 position of the fuse block, inside the door of the controller
-Reconnect the negative wire to the battery
-Test the high output 12 volt receptacle. Plug something in and see if it works.
-It worked. I cleaned up my mess and reinstalled the drawer.
I've been using the receptacle for the last 2 hours, and it works great. No low voltage warnings. The location of the receptacle is a little inconvenient, being under the fridge, but it's better than having no usable high amperage 12 volt DC power at all inside the TT.
Sorry I didn't get more pics.
Have a good one,