How To Connect Ammeter To Battery. Connect the red wire to the 10A20A input port on your multimeter. Unfortunately I didnt find any good resource about how to wireconnect it.

Now for the Battery. Connect the battery and the controller. The guide is likely to be similar for any brand ammeter.
Make a connection between the charger to the ammeters terminal.
Lets first look at what cant be measured realistically from a battery. I had the concept that in order to check the maximum current a battery can supply it is fine to connect an ammeter in series with battery because ammeter has low resistance in series and this will yield the maximum current a battery can supply. A series connection resembles a closed loop a necklace would be a good example. In case it is ina.

