Some general battery and solar questions

[davey307]

I have 2 - 12 volt lead acid batteries in parallel , i want to replace them with 2 - 6 volt deep cycle AGM in series

My premier has the original converter for the shore power connection. Will this charge the AGM properly? Any potential issues?


I also want to add solar next, any considerations that i should look at as to not having to redo first step?


Thanks

[chin_k]

I think some charger use a slight different charging curve for AGM, but it is close enough that most can interchange them without much problem. As for going from two 12 V in parallel to two 6 V in series, both will look the same to the rest of the system, so there is no need to worry. The amperage (A) of each of the new should be doubled or more for you to get the same capacity compare to the 12V batteries.

When you add the solar, I don't think there is anything that you need to redo that is not already taken off .

[Roly]

Hi Davey,

You'll see in here, as well as other RV forums, that many folks have upgraded from the original (Probably Magnatek 6345) charger/converter to a much smarter Progressive Dynamics 4645 slide-in.

The life of your deep cycle batteries in enhanced by charging with 3 or more stages. The PD unit is not programmable, like some stand alone smart chargers, but has reasonable parameters. I installed one a couple of years ago, and installed a small solar system since, finding that my solar controller is programmable to a battery manufacturer's recommendations, it serves to "finish off" charging from other dumber sources like engine, or generator. Search through this forum and you will find lots on the subject.

Roly

[chin_k]

Oh, I see. Yeah, I got the Progressive Dynamics inverter in my rig too. The original one does not do well in trickle charge, so it has a tendency to boil off the water in the wet cell of the lead acid battery. I don't know if it will harm the AGM as much long term, however. Any one know the answer, I will be interest to hear about it.

[ngpsaki]

How hard is it to replace the converter-charger? Any tips to make it easier? Any cautions I should know?

[caconcourse]

How hard is it to replace the converter-charger? Any tips to make it easier? Any cautions I should know?

I described the procedure in my blog, with some pictures:

http://clayrushing.com/2017/01/21/chino ... -upgrades/

It was pretty straightforward, except I should have pulled a little more slack in the main DC power and ground wires before installing the DC distribution card to make it easier.

[ngpsaki]

caconcourse, I studied the pictures on your blog and need a little clarification. On the Magnetek board, I see two white wires coming up from the bottom. On the "after" pic, I see three white wires, one from the bottom and two from the top. Where did the third wire come from?

[caconcourse]

caconcourse, I studied the pictures on your blog and need a little clarification. On the Magnetek board, I see two white wires coming up from the bottom. On the "after" pic, I see three white wires, one from the bottom and two from the top. Where did the third wire come from?

There are only two white wires on the "after" pic. The wire you see on the bottom goes behind the back of the card and is the wire on the top right, on the connection labelled "CONV" (for Converter).

The black wire also comes up from beneath, behind and over the top of the card, to the connection labelled "POS+". In the 12V RV wiring, whites are usually grounds (-), and black is the hot wire (+), but often wires are modified, so you need to test and not assume. In the case of this conversion, it is simply a matter of moving wires from the + connection on the old board to the + connection on the new board, etc. Taking before pictures helps in case you forget.

The large red and white wires are the battery connections, and are the ones that needed an extra inch or two to reach the new connections that are on top of the new card instead of the bottom of the old card.

PD Distribution Card

[ngpsaki]

You're very generous with your time, so I hope you'll forgive two more newbie questions.
1. What's the easiest way to disconnect the coach power? I saw one video where the person disconnected only the negative cable from one battery. Is that all that's needed?
2. Do I also need to disconnect the starter battery?

Sorry for the dumb questions, but I don't want to break anything - including me!

[caconcourse]

You're very generous with your time, so I hope you'll forgive two more newbie questions.
1. What's the easiest way to disconnect the coach power? I saw one video where the person disconnected only the negative cable from one battery. Is that all that's needed?
2. Do I also need to disconnect the starter battery?

Sorry for the dumb questions, but I don't want to break anything - including me!

Make sure the shore power cord is not plugged in, and you can shut off the DC power with the "Store" button on the overhead switches in the cab. Check for power with a voltmeter on the big red and white cables and if there is no power, you should be safe.

You shouldn't have to disconnect the starter battery for this job but you can if you like. Removing the negative cable should be sufficient.