Community Forums

chunker · 10-29-2017, 10:32 PM

We just got back from a 3 night boon docking trip there again. It was cold and a football weekend so we ran the generator more than normal. Overnight the house volts would drop to 11.5. Generator would start right up. When I got back, parked it under the pole barn and didn't plug in. I also turned of the house batteries by the door. Assuming it kills al house 12v I'll see where I am tomorrow. 2 hours after parking the volts were 12.5. I suspect the batteries are growing weak. Good enough for RV park staying but weak for boon docking. We really need the electricity at the site but held up by county permitting bureaucracy.

In the next week or so I'm going to do some tracing based on the suggestions here.

chunker · 10-30-2017, 09:56 AM

Update on batteries. So overnight the coach was parked with a fresh charge and the battery switch turned off. To my knowledge all 12V was disconnected. This morning about 10 hours later my multimeter says 11.9V. Turned batteries on and inside reads the same. Today I'm going to fully charge the batteries, disconnect the cables and see again what the voltage individually is tomorrow morning. I know I bought cheap batteries and if I'm going to do any boon docking I'll have to replace them.

Thinking about 6V but also would have to add/change/modify the cables. Ignorant at this time what 6V cables or posts look like. A previous comment talked about replacing the 3 12V with 4 6V, would 6 6V fit or is that overkill? Not sure if a person can have too much capacity. Guess I'll go plug into the 50amp and start the charging.

chunker · 10-30-2017, 12:58 PM

Another update, after charging a few hours and getting the charger up to the float stage, I turned the batteries off and disconnected the negative cables. 2 check at 12.7 the third 11.9. Hmmm. Bad battery dragging the other's down. 2 of them are 2+YO and one 1YO. I think I'm going to rearrange the batteries and put the bad one on the outside, currently the inside one of course, and leave it disconnected. I'll try the next trip with just 2 batteries and see how that works.

Then I'll have to decide between 12V AGM or converting to 6V. I would be interested in hearing from those who have switched to 6V and the connections and cabling used.

Thanks

PS, how many also. Not sure of size recommended so don't know if 6 would fit on the tray.

Kiawah · 11-05-2017, 12:10 PM

Sounds like you are zeroing in on the real problem.

My coach came with four 6-volt batteries, and I added two more.

Two 6 volt batteries wired in series (to make 12v), typically have more amp-hrs capacity than Two 12-volt batteries wired in parallel. The reason is in the physical length of the battery case, with only 3 cells (each 2.2 volts) in a 6 volt batteries, the internal plates in the batteries are thicker.

You just need one little short battery cable to connect the two 6volt batteries together in series, to make up the 12v.

A lot is going to depend upon what space you have available to mount batteries in. If you have space for 4 or 6, I would definitely shift over to 6 volt batteries. If I only had space for 3 batteries, I guess I'd compare the capacity (and cost) of 3 (12v)wired in parallel as you have right now, compared to 2 (6v) wired in series.

Winemaker2 · 11-05-2017, 03:04 PM

If you are debating 6 vs 12 V take a look at this post and cobrainwd link re deep cycle batteries.
http://www.irv2.com/forums/showthread.php?t=365954
6V Golf cart batteries are by far the best choice for house loads especially if you do dry camp.
You should already have sufficient jumper cables from your 12V. Battys. If using 2 - 6V only need one jumoer to connect one pos to other neg so you get 12 V.
If you have room and go w 4 - 6Vs you duplicate the first pair in series and then parallel those 2 banks.
Also best if you go w 4 to hook up you neg MH connection to one bank and The Pos MH connection to the other.
That balances the two banks and will have longer life.