Hot Alternator

[Captain Crunch]

Hello there, Just installed a new Balmar 100 amp alternator. Seems to be getting really hot and battery bank # 2 doesn't seem to be holding a charge very well. Will this alternator keep trying to charge batteries that wont hold much charge and get really hot or does it charge the batteries(because they won't hold much charge) up fast and step down to a float voltage and there is something else going on. We are using a xantrex external reg. The alternator has a internal smart reg for back up that is manually switched ,in case of external reg failure, as per the manufacturers instructions. The batteries in question are 3 years old wet cell deep cycles.

 

[Tom Metzger]

These alternators generally run hot. You should use a voltmeter to see what is happening with your regulator. I also recommend a battery monitor if you want to keep tabs on your house bank. It isn't needed for your starting battery.

 

[Cory B]

Alternator temp

I think the Balmar (& xantrex?) external regulators have an optional alternator temperature probe. For the Balmar at least, it will cut alt output by 1/2 if it gets too hot. The balmar probe was about $25.

Ditto on the recommendation of the battery monitor - we have a BlueSeas one that monitors voltage & current for the housebank only... it can keep you entertained for hours.