Charging with your car.

[Killo1]

I'm camping here in Lake Tahoe's Emerald Bay. We've been here for 4 days and I noticed my battery seems to be getting a little low. I have a few more days and have been NEEDING my Fantastic Fan (a little warm out here and not as much shade as Reserve America promised)

Can I use my jumper cables and my running motor from my car to charge my trailer batteries?

If so, how long about should it run to charge to series 24 batteries?

Thanks

[wkerfoot]

Originally Posted by Killo1

I'm camping here in Lake Tahoe's Emerald Bay. We've been here for 4 days and I noticed my battery seems to be getting a little low. I have a few more days and have been NEEDING my Fantastic Fan (a little warm out here and not as much shade as Reserve America promised)

Can I use my jumper cables and my running motor from my car to charge my trailer batteries?

If so, how long about should it run to charge to series 24 batteries?

Thanks

Killo1,

It will take a while to charge your trailer battery, it will probably be faster to use jumper cables off of your car, however probably safer to plug the trailer plug into the car. Some newer vehicles are tempermental when it comes to using jumper cables.

Bill

[john hd]

alan

is your tow vehicle wired to charge the trailer?

if it is just plug your umbilical cord in and let the tow vehicle run for 1/2 an hour.

john

[CanoeStream]

Alan -- Indications of low battery power would probably suggest you are south of 40% charge, a damage zone for lead-acid batteries. Like John says, hook up your umbilical you use while towing and run the car engine.

Tow vehicle demands on an alternator can make one drive 150-200 miles before being fully recharged from what I've heard. Perhaps an idling engine is capable of diverting more to the trailer battery. John, would you say Alan should repeat the 1/2 hour treatment a couple times and then see how it goes?

I do know that a vehicle's healthy cooling system is not taxed at idling like it is under load, so Alan should be able to monitor it while charging and feel safe if other indicators look right. Turn off all TV accessories of course.

[john hd]

i agree bob. a couple of times wouldn't hurt!

john

[Druupy]

This was discussed last month. A link to that:

http://www.airforums.com/forum...ghlight=jumper

The short answer, it takes 6-8 driving hours to charge your trailer for a weekend. That seems to be how the airstream systems were designed.
2 one hundred amp hour batteries at 40% charge will need over 100 amp hours of charge. The "pigtail" trailer lighting plug will only charge at 8 amps per hour, that equals 12 hours.
The jumper cables charge at 20-40 amps per hour depending on vehicle and length/size of jumper cables.
If your gonna pigtail charge for an hour, why not jumper charge for an hour, and see which way works best?

[ibedonc]

fyi , sound like you need a Solar panel , I just got a 125 watt one for mine

not sure if I am going to mount it or make a setup I can carry in my truck , like a pole I can mount to A frame somehow , will use it on my home system , when not in use with AS

[markdoane]

Alan,

If your tow vehicle is equiped with a battery isolator, it will take a long time to recharge the batteries through the umbilical cord.

I would use the jumper cables, following all the normal hooking up precautions.

The voltage drop due to an isolator, plus the small (#10) wire and length of run, means the charging voltage available at the coach batteries is usually around 13 volts. You'd get much better voltage, and faster charging, using the jumper cables.

So I'm agreeing with Bill, just giving you more information than you probably need.

[Pick]

According to my chart that came with my Intellicharger, it takes a 55 amp model 18 hours to fully charge a 125 amp hour battery in "Boost" mode which is about 14.4 volts. I am assuming that they are not pumping the full 55 amps into the battery.

[Chaplain Kent]

Please check the water level in your batteries before charging. You also might ask the ranger if they would charge the battery for you. Sometime they have a charger available. While camp hosting in June I charged many batteries for folks.