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Brightsbane
03-07-2015, 05:51 PM
I have a Xantrex Truecharge 20 permanently installed in the boat (Mustang Clubsport 2200) which has a "Flooded" and "Gel" setting. The instructions say that if your batteries have filler caps then to set it to flooded and vice versa.

My starter battery is a Seamaster Gold MFM70 maintenance free which does not have filler caps and my house battery is an Interstate SRS27 which does have filler caps.

From my knowledge they are both flooded type batteries however going by the Xantrex instuctions I should set it to gel for the Seamaster and flooded for the Interstate.

I guess I could set the battery selector switch and charge one at a time but it would be a lot simpler just to put the switch to 1&2 and charge both, but what setting to select on the Xantrex?

tenzing
03-07-2015, 10:05 PM
I Have the same unit and I think you would probably have them both set to lead acid ( flooded)
It will charge two different types as long as they can tolerate the same charging technique/voltage
The difference in the charging routine for flooded and gel is in the order of .2 to .3 volts
If it is permanently installed then it should be attached to both batteries anyway and you need to keep the isolators turned off as per the instructions.
Mine has been going strong for years and really makes keeping the batteries in good condition just a case of plugging the boat in and leaving it.
Cheers
Brendan

Brightsbane
03-07-2015, 10:41 PM
Thanks Brendan, ok I can see that because the Xantrex is hooked up to both batteries then the isolator switch won't make a difference but can you clarify about having it turned off?
The instructions say "If possible, disconnect all loads from the battery", so I assume that if I'm overnighting in a marina and want to top up the batteries from shore power I'd still be ok to run a couple of lights or use the water pump for the sink etc or should there be no load on the batteries while they're charging?

tenzing
04-07-2015, 07:31 AM
My isolator setup is separate on and off switches for house and start, and a parrallel switch. All of these go to the off position.
As Per the load overnight.I certainly hop in and turn the lights on while its charging, but the instructions indicate that you should not really have any load on the battery whilst charging. Make what you want of that , I dont pretend to know enough to guess what the consequences of ignoring this are.
Cheers

Yobbo70
04-07-2015, 07:44 AM
as long as your load does not exceed the 20amp that is being supplied by your battery charger you will be fine, xantrex are designed for this use