Battery to power trailer hydraulics & winch

[Gary_in_Indiana]

<font color=blue>"If your alternator is 64+ amps, I don't see why there would be any problem"</font color=blue>

Chris, can I assume this is based on automotive/electrical engineering expertise on your part? /w3tcompact/icons/smile.gif Also, in a two battery system (which would be what I would effectively be creating here) isn't there typically some other equipment required to accomodate the two batteries?

 

[Bird]

Gary, RVs (travel trailers and 5th wheel travel trailers) have a battery in the trailer to power lights, water pump, fans, etc. And every one I've ever had any experience with was wired so that battery was charged by the towing vehicle. And when parked, if the trailer light plug was left plugged in, you could draw off both the trailer battery and the truck battery (so most folks soon learn to unplug that plug even if they don't unhook the truck from the trailer so they can't accidentally run down both batteries). If you're not familiar with doing the wiring yourself, check with any RV dealer and get it done. Since you say you can power the trailer lift with the truck, it sounds to me as if it may already be wired properly.

 

[bgott]

When you go to the RV store tell them you need a battery isolator. An isolator lets the trailer battery charge while the engine is running but cuts the power from the vehicle battery when the engine is shut off. It keeps you from killing the vehicle battery.

 

[bgott]

http://www.campingworld.com/browse/skus/index.cfm?skunum=6686

 

[Bird]

Good point that I forgot, Brad. When I was traveling full time with the 5th wheel, I had a one ton dually "camper special" Chev. with dual batteries under the hood and the isolator so that even when I left everything hooked up, I was using the trailer battery and "camper" battery on the truck, but couldn't accidentally run down the startin' battery.

 

[Gary_in_Indiana]

<font color=blue>"Since you say you can power the trailer lift with the truck, it sounds to me as if it may already be wired properly."</font color=blue>

What I have is wiring going from my truck battery to a connector on my back bumper. (The original purpose of that was simply to power my winch when I used it back there.) When I got the trailer I ran wiring from the trailer battery out to the tongue and attached a mate to the aformentioned connector to that wiring so I could use the truck battery as a back-up. Do I understand you correctly in that I should be OK to charge with this setup as well (especially if I get the isolator)?

 

[Gary_in_Indiana]

<font color=blue>"you need a battery isolator"</font color=blue>

That was the term that kept eluding me. /w3tcompact/icons/eyes.gif/w3tcompact/icons/blush.gif Thanks for that and for the excellent explanation of how one works. /w3tcompact/icons/smile.gif

 

[Soundguy]

I don't claim any special automotive expertiese, but the electronics comes from college and endless tinkering. Before I changed my major to civil engineering, I was in for electrical eng. For the most part, electronics is electronics.. application is the biggest difference. You will want other support equipment.. a battery isolator and/or a ( 1 or 2 or both switch.. ).. many isolators have a dual battery switch built in. An rv parts place can probably help you out.

Soundguy

<font color=blue>"Chris, can I assume this is based on automotive/electrical engineering expertise on your part? Also, in a two battery system (which would be what I would effectively be creating here) isn't there typically some other equipment required to accomodate the two batteries? "

 

[hazmat]

<font color=blue>You will want other support equipment.. a battery isolator and/or a ( 1 or 2 or both switch.. ).. many isolators have a dual battery switch built in. An rv parts place can probably help you out.</font color=blue>

The reverse is half true. Most 1 or 2 or both switches (not labeled as isolators just called battery selector switches) are somewhat isolated. A marine store is also a good place to look & will have weatherproof switches (might be more $$$ than RV).

The switches isolate when you select 1 or 2. When you pick both, the higher voltage battery will try to charge the lower voltage battery. It is best not to use the Both selection unless your alternator is running.

These switches are usually rated to carry big amps.

<A target="_blank" HREF=http://www.boatus-store.com/browse/category/default.asp?IID=3203>boatus</A>

 

[Soundguy]

Two big diodes solve that problem.. hence the need for the isolator. Many of the dual battery isolators i have seen, are just that. Both bateries are prevented from cross drain, but are connected to the load in common... fairly easy in dc electronics. Different charging schemes can be used depending on exact setup

soundguy

<font color=blue>"The reverse is half true. Most 1 or 2 or both switches (not labeled as isolators just called battery selector switches) are somewhat isolated. A marine store is also a good place to look & will have weatherproof switches (might be more $$$ than RV).

The switches isolate when you select 1 or 2. When you pick both, the higher voltage battery will try to charge the lower voltage battery. It is best not to use the Both selection unless your alternator is running."