How to test polarity of a protected charge port

If you’re like me and you’re second guessing your wiring but your BMS “hides” the pack voltage from your charge port, here’s how to use a multimeter to determine the positive and negative pins.

This info is straight from Kevin @ENNOID - we should ask Joey from Z-Batt to confirm this works for his BMS as well.

Put your Multimeter into Diode Test Mode, and then try the pins. If you connect the red port to the charge port positive, it should read 0L, but if you connect the red to the charge port negative it will read a small Voltage (~0.5-0.6)

Reverse wiring:

Correct wiring:

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