Permanent Site - 12v Efficiency

[rdhetrick]

Hi all,

I have a permanent site where I have a 5th wheel set up. My question revolves around the 12v system.

I know the factory converter/charger is horrible as far as a charger, but I'm thinking efficiency on two scenarios:

1. Disconnect the battery and use the existing converter to power all the 12v needs.

2. Disconnect the converter/charger unit and use a standalone charger to maintain the battery, and power all the 12v from the battery.

I guess this comes down to how efficiently the factory converter converts 120v to 12v versus how efficienty a smart charger can convert the 120v to 12v.

The fist scenario is very simple, no battery maintenance to worry about. I'm interested in exploring this as I am starting to gear up towards boondocking in the future.

Any comments are appreciated.

Thanks!
Rob

[JimK-NY]

If the battery is being overcharged, you need to adjust or repair the electrical system. My charger takes the battery to 13.3v which is not really sufficient. I also have a solar system that I set at 13.7v

[FireGuard]

If you have access to shore power put a trickle charger on the batteries.
Or, a solar panel would probably work.

[Nolan]

Another thing is your refrigerator/freezer. Depends on what you have. We found out when our factory converter/charger took a dump and we shut off the batteries to save them that our refrigerator/freezer won't work. Needed the batteries for the control panel.

We bought a three stage smart charger/converter.

[beemerphile1]

rdhetrick wrote:
Maybe I didn't explain the question very well.

Yes, when moving it, the battery needs to be installed. But when stationary and plugged in for 6 months or more at a time, the factory converter/charger will overcharge the battery and cause offgassing. The battery has to be looked after and topped off with water. It's pretty well known that the factory chargers are poor at best.

The point of the question is efficiency. There are going to be losses when converting from 120v to 12v, and my question was basically which has less losses - a factory converter, or an aftermarket "smart" charger?

Thanks again

If we had a clue what RV you have and what brand and model converter you have, we might actually be able to answer your question rather than make wild guesses.

How about some information in your signature or profile?

[Clay_L]

I bought a Progressive Dynamics PD9245 45 amp three stage converter/charger/float charger with the charge Wizard. It goes into float mode that maintains the batteries without causing outgassing or damage. It is also a decent charger with a bulk mode at 14.5 volts dropping to 13.5 v and then 13.2 v. One unit makes things simpler than carrying extra stuff. Higher current models are available.

[rdhetrick]

It's a 2007, I think the converter is a WFCO 60 amp.

colliehauler wrote:

rdhetrick wrote:
Maybe I didn't explain the question very well.

Yes, when moving it, the battery needs to be installed. But when stationary and plugged in for 6 months or more at a time, the factory converter/charger will overcharge the battery and cause offgassing. The battery has to be looked after and topped off with water. It's pretty well known that the factory chargers are poor at best.

The point of the question is efficiency. There are going to be losses when converting from 120v to 12v, and my question was basically which has less losses - a factory converter, or an aftermarket "smart" charger?

Thanks again

Older converters that was a issue but modern converters not a problem. What year rv? I keep a battery in my rv that sits on my seasonal site.

Agree with sch911 on battery acts as a capacitor. You have sensitive electronics in your refrigerator board and furnace board that can be expensive to replace.

[colliehauler]

rdhetrick wrote:
Maybe I didn't explain the question very well.

Yes, when moving it, the battery needs to be installed. But when stationary and plugged in for 6 months or more at a time, the factory converter/charger will overcharge the battery and cause offgassing. The battery has to be looked after and topped off with water. It's pretty well known that the factory chargers are poor at best.

The point of the question is efficiency. There are going to be losses when converting from 120v to 12v, and my question was basically which has less losses - a factory converter, or an aftermarket "smart" charger?

Thanks again

Older converters that was a issue but modern converters not a problem. What year rv? I keep a battery in my rv that sits on my seasonal site.

Agree with sch911 on battery acts as a capacitor. You have sensitive electronics in your refrigerator board and furnace board that can be expensive to replace.

[rdhetrick]

Maybe I didn't explain the question very well.

Yes, when moving it, the battery needs to be installed. But when stationary and plugged in for 6 months or more at a time, the factory converter/charger will overcharge the battery and cause offgassing. The battery has to be looked after and topped off with water. It's pretty well known that the factory chargers are poor at best.

The point of the question is efficiency. There are going to be losses when converting from 120v to 12v, and my question was basically which has less losses - a factory converter, or an aftermarket "smart" charger?

Thanks again

[sch911]

Some converters don't work well without a battery. Also, the battery acts like a giant capacitor to smooth out voltage transitions and fluctuations with larger load cases. I would never consider removing it. But rather maintain the battery correctly....

[colliehauler]

I guess I don't understand. If you have 120 volt power why is this a issue? The battery would be maintained by the converter and supplement high power draws such as moving the slides. If you pull it you need a battery for the breakaway switch.

[darsben]

1 is almost the best answer. The battery may need to be inline for things to work. Slides ETC. Give it a try by disconnecting negative side of battery