charging trailer batteries

[Blue Ox1]

hey guy's I'm in the process of setting my truck up to pull the new camper and was wonder what size fuse is used to charge your trailer batteries?

Joe

 

[B.G. Smith]

I believe mine has a 40 amp fuse which carries the trailer brakes and lights/charging. You want to set up the trailer brakes on an auto reset breaker and the charging line really depends on the wire size you use. #10 wire is good for 50 amps. bg

 

[bkroupa]

I used a 30amp circuit breaker.

 

[K5IP]

If your trailer battery is depleated when you plug in to the truck, the momentary inrush current which lasts for only a few seconds can be enough to trip a 30A fuse.

An auto reset breaker solves this and is a great solution. Available at most auto parts stores.

Rog

 

[Blue Ox1]

I have the charge wire wired in to it's own space off of a fuse block and use a relay to control it. I was thinking about using a 5 or 10 amp fuse for a battery charge,I'm afraid I will over charge the battery using a 30 or 40 amp

Joe

 

[macdaddy]

The 05's have a 15 amp charging line in the (six flat one round) factory trailer plug for charging while you tow I believe the 1st gen trucks are aswell. The shore power plug will either be a 30 or 50 amp breaker, depending how big your trailer is and how many A/C units ETC you have.



Mac

 

[Bill Stockard]

In 1992 when I rigged up the battery charge line on my new D350 CTD to tow my 5th wheel, I used 8 gauge wiring directly from the truck's battery, both positive and negative, to the 7-way RV receptacle in the truck bed. On the positive line, I installed a 40 amp circuit breaker near the battery and a relay similar to this one http://www.tekonsha.com/product3.html

to prevent the truck's cranking battery from discharging while parked. The relay was activated when the ignition was turned On. Do not use a starter type relay as they aren't designed for continuous duty. I never had any problems with this system, no dead cranking battery, and the batteries in the 5th wheel were always charged up after a few hours of towing the trailer.



In theory, the all batteries should equalize, but in reality the trailer battery remains at a slightly lower charge level because of its distance from the truck's alternator.



Bill