Battery charger set to constant 13.5 volts

[Jared1048]

Hi,

So I have a Xantrex TrueCharge 40 (old model) and its got a setting for 13.5 volts to act as a power supply (as stated in manual). My question is why?

Last time I checked the water in my batteries it was pretty low between all the batteries. I put an entire gallon between the 4 batteries ( 6 volt golf cart). I am a liveaboard and think that when we are using electricity that it makes the battery charger think the batteries are lower than expected and is possibly overcharging them which is causing the excessive use of water?

The battery charger has 3 settings thee step, two step or 13.5 fixed output. What setting should I set it to?

To add to the lunacy I've got an AGM as the emergency backup which is a different battery type than my wet cell house bank. I've set the charger to flooded for charging characteristics which is probably ruining the expensive agm.

I do have a battery temp sensor though. I have my banks set in the rear starboard laz. and two in the engine compartment. I have the sensor in the warmest location (shared with engine).


Thanks,
-Jared

 

[Stu Jackson]

Jared, that 13.5V setting is made exactly for your liveaboard power supply setup. It reduces the voltage to avoid boiling off the water from your batteries.

Lunacy? Not really. Many skippers have AGM reserve banks. The charging voltages between wet cells and AGMs are very close. Go to www.balmar.net, download any regulator manual and the manual will have the recommended charging voltages in a large table.

 

[Dan Hill]

I would set it to the three stage option for bulk, absorption, standby voltages appropriate for your batteries.

You may want to consider a separate charger for the AGM or possibly replace it with one comparable with your house bank makeup.

 

[Bill Roosa]

Actually the 13.6 is designed to power equipment when the batteries are removed for the winter. Also allows you to power 12 volt appliances when one the hard and the batteries have been removed for the winter. Or so the manual says

 

[Maine Sail]

Actually the 13.6 is designed to power equipment when the batteries are removed for the winter. Also allows you to power 12 volt appliances when one the hard and the batteries have been removed for the winter. Or so the manual says

It is also very useful when at the dock, after the batts have been charged, to prevent the charger from re-entering absorption when a DC load bumps it out of float.... These chargers are really pretty dumb and the absorption cycle uses a timer based algorithm..

 

[Jared1048]

It is also very useful when at the dock, after the batts have been charged, to prevent the charger from re-entering absorption when a DC load bumps it out of float.... These chargers are really pretty dumb and the absorption cycle uses a timer based algorithm..

Yup, that's what I was thinking. Thanks for confirming!

-Jared