Firstly,turn the knob to the corresponding position according to the battery quantity
You will Charging, then plugging in the batteries in sequences "1-2-3S...", finally connection the series board to the Charging with cables.Example: You have 3 batteries to Charging, firstly turn the knob to "3S" position, then plugging the battery into port 3S in sequences, and finally connection it to the Charging with the Balanced cable and XT60 cable.
All batteries should be the same, battery capacity, battery type, brand.
Never leave board unattended while charging or discharging.
Do not Charging over 1.5amps. The fuses is 5A that not means you can Charging it in 5A, the knob is for 1.5A so not Charging it over 1.5A.