Measuring voltage and current from PWM solar controller

Actually I use ACS758 for current.

Now I understand that all GNDs are not connected together in solar controller.

Actually, I am very particular to have all measurement from solar panel, battery and load. I think for my circuit, I have to put load reading a way from it with assumption that load measurement is the same with battery.

So, is there a way to measure solar panel voltage and current without having its GND connected to GND of measurement circuit?