Lavezzi 40: Charging House Batteries

[john jeffrey]

The Lavezzi Mon Amie has only a starting battery in the port ER with house batteries in the stbd ER. There is an isolation switch in the stbd ER stating that it should only be switched on in an emergency.
To my mind this is under-utilising the port alternator as it only charges the port starting battery when the isolator is open.
Is there some other reason why we can't charge the house bank using both alternators when motoring?

[DotDun]

Because you will forget and leave the 2 battery banks connected then run down all your batteries. Hence, the reason the switch is labeled for use in an emergency only.

[Sailmonkey]

sure, put a lead direct from the port alternator to house also and use an echo charger or similar to charge the start battery.

Xantrex Technology Inc. - Recreational Vehicles - echo~charge - Product Information

the start battery needs very little charging as you only pull a small amount of total capacity each time you start.

[Ike]

The typical engine mountd alternator is not very good at charging deep cycle house batteries. It will not bring them up to a fully charge and may charge them at too high a rate resulting in overheating and depletion of liquid. You should use a good four stage charger to charge house batteries.