BFL13 wrote:
Did the test on start up with me on meter at the starting batt and DW on ignition key. Voltage went:
12.71, turn key
10.64, then ignition
14.81, then
14.60 etc. All very quickly.
I didn't have a second assistant to watch the amps to house battery, but I am assuming the 37 amps seen briefly yesterday "went with" the brief moment it hit 14.81 volts in today's test.
Certainly amps to the house battery reflect voltage at the engine battery as it changes--see OP results over time for that.
From the replies it seems "it is what it is" --IE, not going to get much better for amps without an extraordinary bunch of (expensive and PITA) modifications.
I will learn from more experience with the Class C in various scenarios whether it would be worth trying to improve the alternator charging to the house battery bank.
You need more data points to verify where the voltage drops off. Only the battery voltages were posted. Need to post the isolator voltages as a minimum and any other terminal points along the charge circuit. This is to determine if you have bad terminals, drop in the isolator, dirty connections or is it just not enough copper between the points of interest. Maybe a relay isolator is needed instead of an old diode based.
So put a 25+ amp load on the house battery, run the alternator and start poking around with the voltmeter. Use house battery negative to reference ground.
