Dashboard Alternator light

BFL13 wrote:

I think you have it backwards. If you idled for a while the alternator voltage would taper to 13.8ish. meanwhile the PD set to 14.4 might eventually get the batts to near that. with voltage drop on the PD wiring you might never see 14.4 at the battery even with the low amps at the high SOC meaning almost no voltage drop.

Solar's low amps means little voltage drop unless thin wiring, so you could set that to 14.5 and get 14.4 which might ot set off the light.

You have to test for how high you can set the solar without the light coming on when the house batts are full. If they are full you don't need to be doing that at all, so if you did have a way to turn off the solar when the house is full while driving, you could get to the campground with the house full, no red light, and alternator charging looking after the starter batt.

BTW, do you have the charge wizard or pendant to make the PD do 14.4? If not, it will only do 13.6. What are you doing with that for testing?

When I started the RV, the voltage at the starter battery dropped from 14.3v to 14.25v. What I meant was that if I was more patient, I could have idled the engine until the PD brought it up to 14.4v to see if 14.4 would set off the light. I've seen 14.4v at the starter battery on the monitor but not with the MH engine running at the same time. The highest I got today was around 14.25v at the starter battery with both the converter and the alternator running. The current was about 6 amps.

I'm not sure what you mean by low amps from solar. Granted, it's not converter amperage but the potential is there for almost 25 amps.

My cheap controller doesn't give me much choice is to how high I can set voltage. Tops is 14.6 (Flooded profile) 14.4 (Lithium profile, no float) and 14.2 (gel profile). This test was just to see if lowering the voltage from 14.6 would keep the alt light from illuminating and it seems to. Setting the profile before traveling is not tough. Turning the panels off while drive requires pulling off the road. I didn't anticipate this issue. Now when I first noticed this problem, my batteries were full. The light might have gone out shortly anyway if I hadn't pulled off and shut the solar down or as Doug suggested, the voltage output from the controller would have dropped to 13.something in 2 hours.

My PD converter has the Charge Wizard.