Battery and shore power

jacade

When using shore power sbould I switch the disconnect on the battery to off (red) or leave it in the on position (green)?

Vegascacher

You can leave it in the on position.

Nomad

On - The converter will keep the battery charged.

Cyclonic

Yes, leave it on, the converter will go into a float mode and keep it charged.

DouayHA

Is there a point where you would want to turn it off if you are leaving it plugged in long term? Say over several weeks in between trips or during the winter?

Ratkity

The only major risk is running your converter all the time.. does that reduce lifespan? - I don't know. The other thing I've "heard" is that you can boil off your distilled water in your battery. I think this is a myth and I've barely put a few tablespoons of diH2O in after winter weather and the camper being plugged in the entire time (I live in the east in a fairly mild winter).

My AGM battery on my motorcycle needs the smart float charger taken off periodically and needs a full overnight charge with a regular charger. Not sure if this is something lead acid batteries need periodically. Just my experience.

jkjenn

Ratkity said:

The only major risk is running your converter all the time.. does that reduce lifespan? - I don't know. The other thing I've "heard" is that you can boil off your distilled water in your battery. I think this is a myth and I've barely put a few tablespoons of diH2O in after winter weather and the camper being plugged in the entire time (I live in the east in a fairly mild winter).

My AGM battery on my motorcycle needs the smart float charger taken off periodically and needs a full overnight charge with a regular charger. Not sure if this is something lead acid batteries need periodically. Just my experience.

It seems like these converters are hit or miss and it could be concluded that more runtime translates to a faster death, but honestly, I am not 100% convinced - it seems hot or miss. I think when mine dies, I will upgrade to a Progressive Industries converter.

Nomad

A couple I met with a T@DA are on there third converter - agree, hit or miss.

Ratkity

I agree PXL and jenn ... it all seems to be hit or miss with converters. I know the lead acid battery water boiling off is a myth. I also know that what my motorcycle AGM battery needs might be may not apply to a camper or RV deep cycle battery. 

Those T@DA's are adorable... I liked the picture of that red one posted here recently. It looked *very* well cared for!! Unlike the dirty thing sitting beside my house right now.

wizard1880

It's no myth the battery acid boils off.  Just not as quickly as some would expect.  If you have a converter on the fritz and it's stuck at 14.4v, the battery will boil dry in a matter of weeks.

Here's a little science behind lead acids--most group 24 and 27 batteries are marine starting, and have calcium on their plates to resist boiling.  Those with golf cart batteries are lead antimony--longer deep cycle life, but they tend to boil off water much quicker.  I've already added some water to mine and they're only 6 months old with 6 deep cycles.

It's really a good idea to check them at least once a year.

Ratkity

Very good info, wizard. It makes perfect sense that one answer does not fit all. All the generalizations end up being "rule of thumb" and sometimes don't make sense. Since I have an Interstate deep cycle 27, it's probably why it rarely needs much water. I also unplug the camper periodically so the cord isn't in the way during yard work (and forget to put it back for a few days). Always check water before the season starts! Good practice despite it being a general statement (yet again - but it's good one). 

I do worry a little about the converter. Like PXL said, it's hit and miss. So far, no issues for me in 3 campers that have had a converter. One camper lasted 13 years without a problem. I have a negative shunt detecting battery input voltage and checked it often on my last camper (haven't install it yet on new one). I've never allowed the battery to go so low as to see 14.4V in a normal state. It usually stays at 13.2V in float and 13.7V with a load and plugged into shore or solar power.

ScottG

I avoid keeping things plugged in and running when I'm not using them--there's zero likelihood of something malfunctioning or wearing out when it's turned off! A healthy, disconnected battery requires only an occasional top up to maintain its charge.

jacade, I assume you are talking about being on shore power while in camp, and that your disconnect is mounted at the battery (rather than at the converter). While it won't hurt anything to leave the fully charged battery connected, the only semi-compelling reason I've heard to do so is that the battery could mitigate potential low-voltage situations that might damage certain electronic equipment.

If you do disconnect the battery, make sure you turn it back on before you depart. This will allow the TV to top up the battery while you drive, and--more importantly--allows the battery to power your breakaway brakes in the event of trailer separation.

DouayHA, I turn everything off between trips, and over the winter I bring the battery indoors. In both cases I check the charge periodically and top up if needed with a separate smart charger.