Thanks for that information. I had not thought to look at NASA which seems to display the percentage state of battery. It is certanly a lot cheaper than alternatives but do you know if that average can be shown as amp hrs figure and is the shunt on the positive or negative battery lead

I understand these devices monitor a 0 to 50mV signal across the shunt (based on amp hrs) and by sampling this say 4 times per second can maintainan average + or – amp hrs figure over a given time period. This means that it can total up the amp hrs through a circuit but I cannot get a manufacturer to explain if this can show a number on say a charging circuit only.

I wish to total up the amp hrs through a solar panel charging circuit over a 24 hour period. I can fit a shunt to this circuit (and already have one, there are even portable clamp on shunts available). I cannot shut everything else down for 24 hours while I monitor the main battery cable with a shunt.

I don’t know why, but everyone thinks this is a real odd ball idea and beginning to think I’m crazy. I already know the battery state and instant amp hrs reading. All I want to do is monitor and add up a current that is at times off, and when on usually varies between 0.1 and 15 amps. For obvious reasons a time clock cannot do this. This variable current actually happens on a few different circuits both charge and discharge types.

It seems a long winded way to explain but hope you can understand.

Tony Warr
Diatonic B38 Ocean

PS: under duress I had to cut up my grey leather instrument panel and am trying to get a replacment. Any Idea’s