AiLi monitor doesn't like a battery charger?

[metalheaddoc]

My Weize 12V 100ah ran down to 7.8%. I hooked up a 10amp AC charger to charge the battery. My AiLi battery meter froze at 7.8% and didn't move or indicate the battery was charging. When I disconnected the charger, the AiLi was still frozen. I unplugged it and replugged it back in and it works fine. Why would the AiLi care if I hooked up a 10amp changer? If I want to charge the battery via the AC charger, do I need to disconnect the AiLi display?

Jason

 

[sunshine_eggo]

I'm guessing you connected to "not here" and the Aili couldn't see the current going into the battery. When you disconnected power, it reset to 100%.

 

[STW]

Check your battery cable ends. I had an end that was corroded on the inside and it caused this same problem. I crimped on a new end and it works fine now.

 

[metalheaddoc]

So if I connect it directly to the negative pole of the battery, nothing passes through the shunt so it can't measure anything?

 

[sunshine_eggo]

So if I connect it directly to the negative pole of the battery, nothing passes through the shunt so it can't measure anything?

Yes.

All loads and chargers must go where it says (charge) and (output). If the current doesn't pass through the shunt, the monitor can't see it.

Battery monitors work by measuring a voltage drop across a resistor (the shunt). If you don't send current through it, it sees 0A. They compute SoC based on the net Ah flow in or out and the programmed battery capacity.

They do not use voltage except to determine where 100% SoC is.

 

[STW]

Also remember the monitor ONLY reads the battery bank it is attached to. On my RV there is the Chassis battery and the House batteries. These different batteries get automatically latched together by the BCC when the voltage hits 12.9v. The monitor only shows the House batteries because the shunt is on the house battery negative cable.

I mention this because my Solar charge controller was saying I was getting more charge output then my AiLi monitor was showing. I then remembered the above and realized some of the solar current was charging the Chassis battery as well.