Charging house battery from TV?

[JoePfznik]

I am renovating my '69GT and to this point have done enough work (new axle, frame repairs, floor, tires and all running gear issues) to make it tow worthy. It is my intention to tow it from Florida back home to New England before starting work on the interior and on the house wiring in particular. I took the battery that came with the trailer for testing while getting tires mounted and was surprised to find that it still has quiute a bit of life left in it. With this in view, I would like to use this battery to power the break away switch until I complete the design and installation of the final electrical system. Can I maintain the charge on this battery with the auxilary power feed on the seven wire plug to the TV? How should the wiring for this be done and what guage wire should be used? When the TV engine is not running, will the battery on the trailer become a drain on the starting battery in the TV?


Thanks, John

[barts]

Originally Posted by JoePfznik

I am renovating my '69GT and to this point have done enough work (new axle, frame repairs, floor, tires and all running gear issues) to make it tow worthy. It is my intention to tow it from Florida back home to New England before starting work on the interior and on the house wiring in particular. I took the battery that came with the trailer for testing while getting tires mounted and was surprised to find that it still has quiute a bit of life left in it. With this in view, I would like to use this battery to power the break away switch until I complete the design and installation of the final electrical system.

ok.... sounds quite workable. The breakaway battery is often tiny (unless you have disk brakes, whose controller takes a lot more power).

Can I maintain the charge on this battery with the auxilary power feed on the seven wire plug to the TV?

Yes; this is the standard way of doing things.

How should the wiring for this be done and what guage wire should be used?

The main line is typical 10G wire; this is generally sufficient.
The battery is connected via a 20A fuse to the line from the TV. You can go to 30A w/ 10G wire.

When the TV engine is not running, will the battery on the trailer become a drain on the starting battery in the TV?

Most vehicles w/ factory harnesses use a relay to disconnect the trailer power line when the key is not in the running position; my Ford certainly works this way. You can check this w/ a voltmeter or light; this should show that this line has no power from the TV when parked....

_ Bart

[Melody Ranch]

If you charge the battery before the trip you "should" be OK for the trip. Can't really say without knowing the condition of the battery.
You will drain the tow vehicle battery if you leave it connected and use 12v in the trailer when you stop. A real crowd pleaser when you try to start up the next morning. Some newer vehicles have an automatic disconnect to prevent this from happening.