Replacing the house batteries

Forum for both AC and DC electrical components. From engine alternator to dashboard, inverter to batteries, and everything electrical in-between.
TDJohn
Posts: 552
Joined: Sun Oct 27, 2019 11:34 pm

Re: Replacing the house batteries

Post by TDJohn »

Robert K wrote: Sun Aug 09, 2020 3:12 pm Well I got the duracells in after modifying the battery box. Plugged in the shore power and the inverter/converter made a grinding like noise and now no 12 volt from converter. No smoke or burning smell but it probably is not good.
I know there should be a big fuse somewhere.
I don't know if the 4 batteries at 12.7 and the 2 chassis batteries on a trikl start were to much
Bob,

If you follow the positive inverter cable from the battery to the inverter, you should come across a type "T" high amp fuse. Mine is slightly to the drivers side of center, attached to the front of the bed box, in the engine compartment. Yours is probably not that far off.

Before giving up on the inverter, I would suggest to check the 30 amp breaker in your main breaker panel, and also check the 120v ac input connections inside your inverter. Most are mated with wire nuts, combining solid copper wire with stranded wire, that combination is known to get loose, especially in RV applications, and can and does arch out under load.

If you do end up needing an inverter, consider Magnum MS series. It is a premium pure sign wave inverter, that is made in America. It is one of the very few companies, if not the only one, that is still make them in America. I have been very happy with mine. They also make very nifty hybrid inverter that works well for people that do frequent moochdocking on limited power. It assists, and allows you to draw more power than the limited shore power can provide. After the load decreases, it automatically switches back to charging the batteries back up.
John
'95 Serengeti, Cummins C8.3-300
Allison 6spd.
Robert K
Posts: 105
Joined: Mon Oct 28, 2019 2:27 am

Re: Replacing the house batteries

Post by Robert K »

Thanks for the reply John. I
Did not find a fuse inline from the inverter.
The inverter is working just no converter. Will do some more looking for fuse but will probably pull the inverter out.
Will post with any other info
Bob
96 Serengeti 37'
3126 Cat
6 speed Allison
2011 jeep wrangler towd
TDJohn
Posts: 552
Joined: Sun Oct 27, 2019 11:34 pm

Re: Replacing the house batteries

Post by TDJohn »

Bob,

You should be able to check the internal wiring connections without needing to pull the inverter, this might keep you from doing more work than needed.
John
'95 Serengeti, Cummins C8.3-300
Allison 6spd.
wolfe10
Posts: 222
Joined: Sun Oct 27, 2019 4:12 pm

Re: Replacing the house batteries

Post by wolfe10 »

Robert K wrote: Mon Aug 10, 2020 2:32 pm Thanks for the reply John. I
Did not find a fuse inline from the inverter.
The inverter is working just no converter. Will do some more looking for fuse but will probably pull the inverter out.
Will post with any other info
OK, inverter working says the 12 VDC connection between batteries and inverter/CHARGER are OK.

But if no charger function, first thing to check is 120 VAC into the inverter/charger.
Brett and Dianne Wolfe
Ex: 2003 Alpine 38'. Ex 1997 Safari Sahara. Ex 1993 Foretravel U240
Moderator, FMCA Forums 2009-2020
Chairman, FMCA Technical Advisory Committee 2011- 2020
Moderator, http://www.dieselrvclub.org/ (FMCA chapter) 2002-
Robert K
Posts: 105
Joined: Mon Oct 28, 2019 2:27 am

Re: Replacing the house batteries

Post by Robert K »

And now it is charging
2020-08-11 16-23.pdf
(120.55 KiB) Downloaded 277 times
2020-08-11 16-53.pdf
(159.83 KiB) Downloaded 269 times
If my sketches show up the one marked 2 is how I have them wired now
The other is how I had them without charging working
Bob
96 Serengeti 37'
3126 Cat
6 speed Allison
2011 jeep wrangler towd
wolfe10
Posts: 222
Joined: Sun Oct 27, 2019 4:12 pm

Re: Replacing the house batteries

Post by wolfe10 »

Bob,

Better to have the leads that go to the coach coming off different pairs so one pair doesn't do the heavy lifting.
Brett and Dianne Wolfe
Ex: 2003 Alpine 38'. Ex 1997 Safari Sahara. Ex 1993 Foretravel U240
Moderator, FMCA Forums 2009-2020
Chairman, FMCA Technical Advisory Committee 2011- 2020
Moderator, http://www.dieselrvclub.org/ (FMCA chapter) 2002-
TDJohn
Posts: 552
Joined: Sun Oct 27, 2019 11:34 pm

Re: Replacing the house batteries

Post by TDJohn »

Bob,

Either your coach negative cable or your coach positive cable should be connected the the lower pair of batteries, as drawn in your image. As Brett stated, having both the coach positive and negative cables connected to your upper pair of batteries, as drawn in your image, will work that upper pair harder and the lower pair less. Same goes for charging, the upper pair will get the majority of the charge and the lower less so, eventually leading to the lower pair to sulfate and get sluggish, further putting even more stress on the upper pair.

BTW, your two images are wired identically, only difference being that the battery pairing is visually placed differently on the battery tray, so I'm guessing that your charging issue was from something else, or you had a poor connection somewhere. Also, both of your diagrams are lacking proper connection of the coach positive and negative, to promote proper balancing between the battery pairs, as noted in the first paragraph.
John
'95 Serengeti, Cummins C8.3-300
Allison 6spd.
Post Reply