Balmar charging problem?

PekkaL · #1 (**permalink**) 10-10-2007

I have installed a Balmar 6-series 110A alternator with MC-612 external regulator to my Volvo D2-55 engine to charge 420Ah Concorde AGM battery bank and also starter battery. House and starter batteries are separated by battery isolator. Temp sensors are installed to alternator and house battery bank.

I have noticed that sometimes regulator drops charging voltage to zero for undefinied time between few seconds to even 30 minutes. I have thought that the alternator might be running quite hot trying to charge AGM batteries, which should take virtually all amps the alternator can deliver. Therefore I have been thinking that the regulator is keeping zero output to cool down the alternator. House batteries are not warm when this is happening.

I was wondering if anyone have had same kind of problem and if this is normal or if my regulator is defective?

PBzeer · #2 (**permalink**) 10-10-2007

With 3 stage charging, there will be times, when even though the bank is not "full", you will actually be discharging rather than charging. At least, that is my experience. Most external regulators, that I'm aware of, have a timer function for each stage, and though the batteries may be able to accept more voltage/amps, they go to the next stage. I've noticed the same thing with my 110v AC charger, so I assume it's normal. Someone more conversant with electrical issues, may well have a better explaination.

k1vsk · #3 (**permalink**) 10-10-2007

One other possibility could be the sensor on the regulator, particularly if run through the isolator which can result in sensing a false low voltage because of the inherent voltage drop through the isolator

PekkaL · #4 (**permalink**) 10-10-2007

I have connected the sensor after the isolator. It should sense the house battery voltage correctly.

donradclife · #5 (**permalink**) 10-10-2007

When the three stage regulator switches from the higher acceptance voltage (say 14.2v) to the lower maintenance voltage (say 13.4v), the surface charge on the batteries may cause their voltage to be higher than the regulated voltage for a little while, so the regulator turns the alternator off. It should only take a few seconds for the battery voltage to drop down and the alternator (and your tach) to turn on again.