Bestech BMS with e-switch question

I have just made a spotwelded 10S4P with Samsung 30Q pack witha Bestech BMS with an e-switch. I am using a normal SPST Switch for the BMS and when the e-switch cables makes a closed circuit the pack shows 34,4V. When it is off it shows around 29 or 32V. Is this normal? I would assume the voltage to be 0 on the battery output. How is it an on/off switch if it is still able to power stuff?

Same thing happened to mine I was thinking it was a bad batch

I’ve seen that before onto besttech bms’s and a BMS I use from eBay for discharge only. The problem usually goes away after you put a load on the battery pack.

Its normal, if you have no load on your P- You need some loade, to pull the fet. down…


Ah okey! Thanks for the info I’ll test it out tomorrow and set the problem to solved.

The problem was solved by adding the load, it is pulled down to 0V after around 2-3S.

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