How to active lithium BMS?

Thread Starter

Mark Flint

Joined Jun 11, 2017
I have several of these small BMS boards, HXYP-4S-3828. I can't seem to "activate" them. The voltage across the P+ and P– is 11.8v while the actual voltage of the 4 x series cells was 12.99v

The instruction that came with it: "Tips: After the wiring is successful, the board needs to be charged and activated before it has output. "

So far I have tried shorting the P– to the B– because I read this somewhere online. I have done this while the P– and P+ are not connected to a power supply, and also when connected up to a 14.4v supply. When I short the P– and B– when on the power supply the supply starts to show a current is being drawn but not any other time.

Anyone know what to do with these? Thanks.



Joined Dec 31, 2017
P+ and P- are the inputs from a power source to charge the batteries. You need a minimum of 14.4 volts from the spec sheet.
Do not connect P- to B -.