Another fridge question--high DC volatage.

yes and outboard manual charger.

Actually I could equalise by disconnecting the POSITIVE cable because I have 2 pairs of cables: One pair directly the batteries and the inverter/charger and the other from the batteries to the DC Buss.

I suppose that it might work by disconnecting the negative but I suspect that it would still find a return via the inverter and chassis.

I think Don had in mind using an outboard charger directly to the battery. At least I hope so!

UPDATE: I have configured the Xantrex Prosine 2. Equalise Parameters to I @ 5% C and max voltage to 15.0 more like a top charge for now. Battery is at 14.56 at the moment.

Get a DC-DC converter.

dougrainer wrote:
HOW can you equalize if you disconnect the negative cable?????

I don't get that either.

pianotuna wrote:
16 volts may well fry the control boards in the RV (not just the fridge).

Disconnect the negative cable.

HOW can you equalize if you disconnect the negative cable????? That takes the Inverter/Charger out of the battery system. Doug

Anytime you EQUALIZE, it is BEST to disconnect the RV from the coach batteries. Some systems in the RV cannot handle that sustained HI DC voltage that equalizing puts out. There are usually 2(maybe more) battery positive cables on the coach batteries. Disconnect all cables EXCEPT the Battery cable to the Inverter/Charger. That isolates the RV from the equalizing voltage. Some RV's may have the Coach system on one of the Inverter/charger 250/300 amp fuse poles. You disconnect there if so. Just make sure that once you think you have the cables disconnected, you have NO 12 volt power to the coach side of the RV on battery only. Doug

Thanks all, you are right; I knew that back there somewhere but didn't think of it. It all depends on which pair I can reach, the for the battery out OR the Xantrex Inverter/charger input. One pair is at the front of the tray, the other is at the rear, which cannot be accessed without pulling the front two batteries then dragging the inner two forward.

Since I want to get at this as soon as possible, I think that what I will do tomorrow is see if I can set the Xantex parameters to give me 15.2V bulk, absorption AND float, and set the charge current to 5% of C as recommended by Mexicowanderer on his monograph on charging, top charging and equalizing. This will give me time to find (I hope) a 12 A or 24 (25) A manual charger to finish the equalizing.

I might even be able to get the Xantrex to do it, I'll have to play around with that. The whole problem is exasperated by the fact that we leave for a month in Europe in a week.

This has to do with my previous post Yes it's My Own D**n fault.

16 volts may well fry the control boards in the RV (not just the fridge).

Disconnect the negative cable.

disconnect the main NEG cable from the batteries
play safe..the fridge is NOT the only control board
WH and furnace, maybe the even the thermostat

BFL13 wrote:
I would think that if the OFF button works then you can turn it back ON which would mean the controls are "live" on 12v ?

DC voltage range for fridge......10.5 to 15.4 vdc
(what is acceptable to function)

Turning it OFF would leave controls 'live'


I would pull/disconnect DC CB for fridge before equalizing batteries.
Cheaper/easier than new control board/panels for fridge

I would think that if the OFF button works then you can turn it back ON which would mean the controls are "live" on 12v ?