Posted 2016-08-21 4:51 PM (#168107) Subject: charging trailer battery from your truck
Veteran
Posts: 153 Location: Grant City, Missouri
What does it take to get the trailer to charge off the truck going down the road? I have a 2011 Ford 250 diesel and a 3 horse Elite with living quarters.
Posted 2016-08-21 6:33 PM (#168108 - in reply to #168107) Subject: RE: charging trailer battery from your truck
Extreme Veteran
Posts: 448 Location: Los Angeles, Ca.
Assuming you have all factory wiring, the battery is being charged as you drive down the road. However, it is only being charged very slowly and will not bring it to full charge....mostly maintain whatever is energized at the time.....
Posted 2016-08-21 8:34 PM (#168110 - in reply to #168108) Subject: RE: charging trailer battery from your truck
Veteran
Posts: 153 Location: Grant City, Missouri
That is what I thought but someone told me different. I am having battery issues and it isn't working that well. I had a wire loose but my batteries just don't seem to hold a charge very well. They are a little over a year old and I had trouble remembering to plug them in occasionally last winter.
Posted 2016-08-21 9:55 PM (#168112 - in reply to #168107) Subject: RE: charging trailer battery from your truck
Unless you plug it in, (plugged in more often than not) your use will easily out pace the charge your truck produces. The charger in your living quarters is needed to fully charge them. The batteries that are supplied with the trailers are often not the very best to begin with. You might try leaving it plugged in and let them fully charge then get the batteries load tested at an auto parts store. They will likely have to come out to be checked. Letting the batteries run down too far can damage them. You could be looking at new ones, even if they are only a year old.
Posted 2016-08-21 11:55 PM (#168114 - in reply to #168107) Subject: RE: charging trailer battery from your truck
Expert
Posts: 3853 Location: Vermont
Lea Anne - 2016-08-21 7:51 PM What does it take to get the trailer to charge off the truck going down the road? I have a 2011 Ford 250 diesel and a 3 horse Elite with living quarters.
Thanks
About eight hours of non-stop driving...
You will need to run a 10 gauge power wire from the # 4 terminal (12 volt) on the 7-way trailer connector on the trailer to the positive terminal on the trailer battery. This will allow you to maintain a charge on your trailer battery, it will not charge the battery from a discharged state.
Posted 2017-11-01 11:48 AM (#170792 - in reply to #168107) Subject: RE: charging trailer battery from your truck
Location: Wentzville, MO
Also keep in mind that although you're running a 10 ga. wire from the connector, you'll be limited by the wire gauge feeding the trailer connector on the vehicle from the battery. In the latest generation F150's, an 18 gauge wire is used (if you can believe that!)
If you do have a very small gauge wire feeding the 12-v circuit on the vehicle end of the trailer connector, you can simply run your own circuit using 10 ga. wire through a 40 amp breaker directly to the vehicle's battery. As mentioned-even with the larger gauge wire, the distance between the batteries, the output from the alternator and the gauge of the wire will limit the power available for deliver to the trailer battery. You'll be able to maintain a battery, but won't be able to charge it once it's discharged.
Posted 2017-11-03 9:10 AM (#170798 - in reply to #168107) Subject: RE: charging trailer battery from your truck
Elite Veteran
Posts: 720
Wow- 18 ga. What is it rated to carry at that length? Surely not enough to amount to anything. You get a reasonable size older trailer (non LEDs) with several interior lights and you may be at 15-20 amps easy.
Posted 2017-11-03 9:13 AM (#170799 - in reply to #168114) Subject: RE: charging trailer battery from your truck
Elite Veteran
Posts: 720
PaulChristenson - 2016-08-21 11:55 PM
Lea Anne - 2016-08-21 7:51 PM What does it take to get the trailer to charge off the truck going down the road? I have a 2011 Ford 250 diesel and a 3 horse Elite with living quarters.
Thanks
About eight hours of non-stop driving...
You will need to run a 10 gauge power wire from the # 4 terminal (12 volt) on the 7-way trailer connector on the trailer to the positive terminal on the trailer battery. This will allow you to maintain a charge on your trailer battery, it will not charge the battery from a discharged state.
Most living quarters are wired to do this already. If- with your trailer not plugged in to the truck or shore power- AND your horse area lights work- then you are doing this already.
If your horse lights don't work, then the LQ company kept 2 different 12V systems. But most are tied together nowadays.
And in the same vein Paul said- the truck's voltage regulator is reading from the truck's batteries. So if they are hot, then there will only be somewhat of a charge present. It will run whatever load is there generally, but won't do a ton of actual charging of the trailer's batteries.
charging trailer battery from your truck
