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Jeff Jeff is offline
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First recorded activity by BoatBanter: Jul 2007
Posts: 42
Default August 7 - Land, HO!

* Larry wrote, On 8/10/2007 5:36 PM:

This telling little paragraph is why we still have an electrical problem
on the Pig. As soon as we start the engine, we crank it all up BEFORE
the heavy battery charge current and 13V turns into light charge current
and the alternator's voltage regulator starts throttling back rotor
current to limit the voltage to 14.2V.....

Is it any wonder that you're eating V-belts keeping the poor alternator
at its limit BEFORE the battery charging is complete?!

I love you two to death, but we have GOT to stop using our recharging
current to run all that crap! NO UNNECESSARY LOADS UNTIL THE BATTERY
VOLTAGE RISES TO REGULATOR VOLTAGE! RECHARGE THE BATTERIES FIRST!!


I believe this is total nonsense. I have one major load, a
fridge/freezer that draws about 30 Amps and runs about an hour to
three hours a day (depending on air and water temps, etc.). I make a
point of running the engine or generator at the same time as the
fridge, thus saving about 15 to 20% of the power - the efficiency loss
of running the juice through the batteries. In addition to the simple
Charge Efficiency Factor, there is also the issue of running the
fridge at 13+ Volts, as opposed to 12 (or even less) Volts. There is
no indication that the alternator runs harder doing this, in fact its
running about 20% less.

Oddly, you're always claiming that charging a 450 Ah bank at 80 or 90
Amps is doing great damage. What I'm doing is reduces that to 50 Amps
charging, with 30 Amps to the fridge. Are you claiming that the
fridge, radar, and autopilot must be turned off if the engine is
running and the batteries are not fully charged?