charging battery

[reynmts]

hello all! first time on the forum.  I just bought a 2003 rockwood freedom model 1980 that i'm towing with a 2004 dodge dakota.  Should my pu battery get charged while hooked up to the tow vehicle? how can i tell if that's happening? also, any advice on installing a voltmeter inside? I see that they sell plug in models also.  I just didn't know which one works better? Thanks for the help

[wavery]

hello all! first time on the forum.  I just bought a 2003 rockwood freedom model 1980 that i'm towing with a 2004 dodge dakota.  Should my pu battery get charged while hooked up to the tow vehicle? how can i tell if that's happening? also, any advice on installing a voltmeter inside? I see that they sell plug in models also.  I just didn't know which one works better? Thanks for the help

WELCOME TO PUT!!!!

It is not necessary that your battery be charged while towing but it is certainly possible and handy if you have the capacity. If you run your fridge on 12v while towing, it may be necessary to charge while towing. I run my propane fridge while towing.

You would need a 10 or 12 gage hot wire in your trailer harness, going to your battery for charging. Most factory, 7 pin harnesses have this capacity.

The "plug-in" battery monitors work fine but are not very accurate. There are also several different "built-in" monitors on the market. Most would require cutting a hole in your cabinetry to install. I personally use a digital multi-meter to check the voltage a few times a day. You can pick up a digital multi meter for as little as $5 and a decent one is only about $20. They are nice to have for running down electrical problems also:
http://da.harborfreight.com/cpisearch/web/search.do?keyword=multi+meter&Submit=Go

[tlhdoc]

Welcome to PUT!

You should charge your battery with a 3 stage 12 volt battery charger.  Most power converters on PUs do not do a great job charging the battery.  Your vehicle may charge the battery, but again it doesn't charge it that much at one time.  You would need to drive a lot to keep the battery charged that way.  The easiest way to tell if your vehicle has a "hot" line to charge the battery is to disconnect the battery.  Turn on the outside light on your camper, and it should not go on (if it goes on you have the battery connected).  Turn the light off and then plug the tow vehicle (TV) into the camper.  Now turn the light on.  If it comes on you have a hot line to the camper.  On some vehicles you have to have the car running for the hot line to be live.  Good luck with your new camper and have a great time in it.

[reynmts]

thanks for the help guys!!

[tknick]

If you do add a charge line to your 7 way plug, it would be wise to add a relay inline that only makes the charge line hot when the car is running.  That way the PU cannot drain the starting battery in your TV.  If for example you were running your fridge on 12v and stopped somewhere on your trip for some food, shopping, etc, without the relay to disconnect your TV's battery, your PU would drain its own battery and start on your TV's battery.  You would get back in ready to continue on your journey and hear the dreaded rrr,rrr,rrr dead battery noise.  The relay can be purchased from any auto parts store.  there are 4 terminals on the relay.  one for ground, one for 12v source (your TV battery/alternator), one for 12v supply (your PU battery) and one for the trigger (a 12v source on your TV that is only hot when running).

hope this wasn't too confusing.
travis