battery maintainer

For those whose trucks sit.

What do you use?

I was thinking of a HF @ .750 milli amps. Works fine on my motorcycle but that's only 300 amps. Worked good enough to charge my son's car overnight that he could start it without a jump.

But. We're talking 3000 amps on the semi. Autozone has 1 Amp and 2 Amp floaters.


????

 

I installed 3 new batteries 3 months ago and measured draw at .4 positive .25 negative.

.15 draw

18 Pete.


.75 amps would cover it. I'm just concerned with the 3000 amps to maintain. There's no shutoff switch.

 

I'm wondering if the switches cuts power off entirely. Or is there a bypass that keeps the computers running while shutting everything else off.

 

I bought the noco genius 2. But I'm not sure it works properly. After immediate hookup. The red light was flashing. Indicating 25% charge at 12.8 volts after shutdown.

I brought it home to test on my motorcycle agm. It had 13.05 volts from the HF maintainer charger being on it. THE noco flashed the red light. Red went solid at 13.1. After 4 hours it was still red at 13.1.

The manual says 14.5 volts. While can understand 14.0 volts with engine running and electrical loads. I can't see 14.5 being good on a battery not being used for nothing but computer drain. If it even gets there.

If it holds a solid red and 13 volts. I can live with that. Otherwise. I may just go with the HF unit at .75 amps. Since I know it holds at 13 volts.

The batteries are fully charged anyways when it gets parked so it don't have to do much but maintain for the extended park times beyond the typical 2 day weekend.