Battery charging/monitor

[Midsummer_Energy]

Hi There

If your still having issues with your battery monitor NASA BM-1 it would be worth checking to see what AH capacity you have programmed in to the monitor. You mentioned that you have a 540Ah battery bank if the BM-1 hasn't been set to a bank of this size you will get spurious readings.

 

[VicMallows]

Has got me intrigued so checked on the NASA site, as thought you can zero the amp hours used, see page 6 of attached about how to zero it
http://www.nasamarine.com/images/file/BM1+-BM2+.pdf
Hope it helps

Several people have missed the point that the OP has a BM-1 COMPACT. This does NOT have the cumulative A/hr function like the regular BM-1 or BM-2 (and hence the need to zero the accumulative A/hr counter).

(Weird I agree, since surely this is the most useful function of a battery monitor ).

 

[jordanbasset]

Several people have missed the point that the OP has a BM-1 COMPACT. This does NOT have the cumulative A/hr function like the regular BM-1 or BM-2 (and hence the need to zero the accumulative A/hr counter).

(Weird I agree, since surely this is the most useful function of a battery monitor ).

Yes, you are right, had not spotted that, but agree it does make no sense not to have that capacity

 

[legaltender]

Phew thanks for that, I thought I must be a complete idiot not being able to zero the amp hours. The interesting thing is that once the sun comes up, the monitor shows the voltage and percentage charge rising rapidly, even though the amps coming in are not high-at this time of morning 8.45, 2.2 amps with fridges still on and sun from the side. Voltage has risen from 12.4 to 12.8. By about 3 pm, monitor will show batteries fully charged and voltage around 13.6.

Maybe it's something to do with the charging method used by Victron MPPT