Bypassing my BMS (Batterysupports)


I want to bypass my bms I got from Batterysupports, since I only got it for 30amps. I’m using a VESC, so I’ll be using it to make sure the battery doesn´t drain too low.

Just want to make sure I’m understanding everything correctly before soldering everything together. I’ve searched for other threads about this topic, and I think I’ve got it.

Does this look right?

I’m not really sure if I need the “N-” connection on the board. It says “N- with no wiring when charging and discharging are in the same port”, but since I’m not going to use the same port for discharge, do I need to connect N- to negative as well?

Thanks in advance

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Looks right. Mine has the N- too but isn’t used for anything that I’m aware of.

Are you bypassing your bms as well?

If your build is single motor, you should be fine without bypassing it.

It is single motor, but I imagine 30 amps max would be too weak? I’m using an EMax GT5345 motor with 3776w max power. Not saying I want to use all that power ofc, since the fuse on my spark switch is only 40 amps to begin with, but I want to utilize as much power as possible.

I would bypass - the BMS is useless on discharge with a VESC in my opinion and just adds another point of failure.

My plan is to hook mine up for charge only, but for now I’m actually bulk charging at 4.1v (49.2v) and all 12 series cells are staying within 0.01v after many cycles.

I have a feeling (untested, no data to support) the BMS actually helps to unbalance the cells over time, due to a low balance current (30-80ma) and loose voltage controls (4.15-4.25v shutoff).

I’m not keen on using it if I don’t have to. I’m going to continue to monitor the pack without the BMS and see what happens over time.