A simple questions about batteries

Got our new to us TT Saturday...we came home and me and the wife packed up the girls and headed to a local lake camping area.  Great fun and everything went smoothly. 

My hopefully simple question is this:  How does the battery charge on my unit?  Is it charged when we pull it around or does it charge as the unit is plugged in to electric power?

My other question is should be then disconnect the battery when we know the TT is going to sit in storage for more than a few days?

The battery gets charged from the tow vehicle while traveling and by the trailers own charging system (converter/charger) while connected to shore power.

It is generally a good idea to disconnect the battery for longer term storage, a few weeks or more. That will reduce the loss of power caused by small power drains by appliances in the RV.  If it doesn't already have one, installing a simple battery disconnect switch is a good idea.

However, the battery will still slowly discharge even if disconnected. This is a normal thing called self-discharge and may take weeks or months depending on battery condition and type. Be prepared to re-charge when you get ready to use it again.

Also, check the water in the battery cells periodically. Many charging systems, especially older ones, "boil" the battery enough to cause loss of liquid and that needs to be replaced. Use distilled, or at least mineral -free, water.

By the way, check out the RV Forum Library (see button on Menu bar) - there is a lot of good advice for Newcomers to RVing. One whole section is devoted to Newcomers Need to Know.

Hmmm.... I'm not sure how Gary knows the way your rig is hooked up. I can think of several ways that you could show up to a campground thinking you had a full battery and it being less than full.

Your post simply says you have a new to you TT (travel trailer). It doesn't clarify what size or what you're towing with. Small insignificant things like having a 7 pin to 4 pin adapter to match your tow vehicle might take the vehicle charging system out of the loop.

If it was me, I'd want to make sure how it charges by hooking up the rig and checking with a voltmeter that the tow vehicle did charge the trailer battery. And, I'd want to know what parasitic loads might be attached to the TT. Are there smoke, propane, CO detectors attached which do not turn off with the battery switch? Some do, some don't. Particularly with a rig which has been used by someone else, they may have made changes to the sytems.

If your TT sits for a month and the battery is close to discharged, you might not get a full charge just by driving 30 minutes down to the river to camp. Now you're without battery power for the weekend. There's a lot to learn about your rig and my advice is to buy a basic voltmeter for this question and find out for yourself if the tow vehicle is charging the trailer battery. If you have it plugged in, is the charger indeed charging the battery? What is an acceptable level to discharge the battery to, for you. Knowing that discharging it completely, either by sitting or by use, significantly shortens the life of the battery. A 50% discharge on a  deep cycle battery is generally considered the absolute bottom, some suggest 60% or more. Knowing what voltage that is, and how to check it is a good skill to learn.

As Gary says, read, read, read, and check it out so you know for sure about your rig.

Ken

I take my TT battery off when I put it in storage and take it home.  Then every several weeks I put a trickle charger on it for a day or two.  I have a Harbor Freight trickle charger and voltmeter that I use. I found out shortly after we bought our TT that the battery left in the TT would be run down quickly by the monitoring systems. The only downside is carrying a heavy battery back and forth from the storage lot.  I also bought a second battery.  We most often boondock in the national forest and the furnace quickly runs down the battery. And the second battery is often used for an electric outboard trolling motor.   

If you think you will be boondocking quite frequently, I suggest you look into buying a generator to recharge your battery. I have a noisy generator I use to recharge my battery and it is capable of running the AC too. But we normally camp above 9000 ft and it is usually cool enough that we don't need the AC.  Good low noise generator are getting less expensive so you may want to check them out. 

Hmmm.... I'm not sure how Gary knows the way your rig is hooked up.

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I'm omniscient.  :

Actually, the OP said TT (Travel Trailer) and I took him at his word. I suppose that somewhere there is a TT that doesn't have a built-in charging system and use a 7 pin trailer connector, but it would be a rare one. And under 2000 lbs, cause it doesn't have brakes. A TT with electric brakes and an onboard battery will nearly always have a 7 pin plug and provide charging as well as braking.  But yes, I was making an assumption there...  :-[

Yes, disconnect the battery while in storage. The easiest way to do this would be to install a battery disconnect switch. A google search will turn up several .

Thanks guys...it's a 07 Rockwood Roo 26RS.  I don't know what 4 pin vs 7 pin is but I'm betting it's 7.  It does have breaks as we had a break control system installed...forgive me for not knowing the specific terms.

I like the idea of having a trickle charger...we have a Harbor Freight close to my house so I'll look into that.  ALso I do have a small generator...I won it at a Ducks Unlimited event a year ago and have never even taken it out of the box.  I'm thinking for the next several trips we won't be boondocking but going to parks that have the RV hookups.  Since we are so new we could probably just "camp out" in our back yard and it would still be fun.

Gary RV Roamer said:

I'm omniscient.  :

Actually, the OP said TT (Travel Trailer) and I took him at his word. I suppose that somewhere there is a TT that doesn't have a built-in charging system and use a 7 pin trailer connector, but it would be a rare one. And under 2000 lbs, cause it doesn't have brakes. A TT with electric brakes and an onboard battery will nearly always have a 7 pin plug and provide charging as well as braking.  But yes, I was making an assumption there...  :-[

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I could just envision the OP coming back in a couple of weeks with a dead battery story. Since we don't know who set up the connections or even what type of vehicles, it seemed to me to have too many variables. It sounds like you guessed exactly right.

I'm always nervous when the OP starts out with a subject of "A simple question......