Understanding Controller SOC (State of Charge)

The controller in the pic is a PWM, in the image it displays State of Charge (SOC) in the bottom left corner. If you have one of these controllers and it is displaying SOC, have a look at the bottom of the controller and see how many cables are connected, there will be six terminals, if only 4 are being used, the controller is in the wrong mode and will be significantly undercharging your battery. The reason this happens, is that SOC mode can ONLY be used where ALL of your loads are connected to the additional two terminals on the right of the controller. This does not only affect Fangpusun, any controller that looks like this one and is showing “SOC”.

It is a simple fix, you can do yourself. If you use the up/down button and toggle through until you see the battery voltage display, then press and hold the right button for 5 seconds or until the display changes, the screen should show “SOC” now press the up/down button (usually one press) until you see “VOL” now press the right button again and the controller will revert to its usual state and will now show “VOL” in the bottom left and you will no longer see the SOC % display.