My bms wont charge help me

here is drawing of what i did.

it just simply wont turn on. i checked every wire. Vesc works fine. i pluged charger, stays green. could be faulty bms but i wonder if I switched polarity of charging port if I followed my drawings.

Need info: Battery type and specs. bms type and specs. charger type and specs. and test the polarity of your charge plug from the charger with a multi meter and make sure it matches the charger port on your board.

battery lipo 5s5a x4 = 10s10a. getting 40.5v bms charger: 42v 2amp, getting 44v with multimeter.

i check balance lead which is correct order.

i soldered bms with batt- and charger- left p- empty. maybe i should connect p- to something to work?

im thinking i should connect batt plus to p-?

Please don’t do that. Connecting the battery’s positive to P- will short the battery.

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Your charger should only be outputting 42v 44v is too high and it sounds like you have a defective charger.

Another reason for your battery not charging completely is if the cells are too far out of balance.

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i charged the batt before put them to gether they are with in .1 to .15 differences. may be the charger problem :(. i hav besttech bms on the way but cant figure what the problem is

Was this ever solved? I seem to be having the same issue. @Namasaki or @onepunchboard any thoughts?

In my case I can get my VESC powered and my motor running when it is on the charger but nothing works when I unplug. I am using a Bestech BMS with E switch and a 10s5p Li-ion config. My cells are all balanced and if I unplug/plug the balance cables from the BMS the charger begins charging for ten second before stopping.

frankly i gave up using bms for that. besttech bms shouldn’t be the problem but not sure why such problem occur.

So what’d you do? I am at a loss as my board is basically complete but I cant take it off the charger!

If you unplug the balance connector while the bms is on, it will go into protection mode and you’ll have to cycle it off and on to reset.

Try this sequence

1:Turn the bms off. 2:Connect the balance connector to the bms. 3: plug your charger into the charge port 4: turn the charger on and then immediately turn the bms on. 5: when charging is complete, turn the charger off then turn the bms off and wait for the system to drain off residual voltage and then unplug the charger from the charge port.

That didn’t seem to do anything…

Double check your wiring then. Especially the balance wires.

All balance cables are showing correct voltages, the charger is correctly showing 42.5V. I believe all my solder joints are correct? But I could be wrong, Ill post a picture and the wiring diagram I used

Here’s some pictures of my Wiring and then here are my BMS specifications

And the wiring diagram I followed

@RedEagle @Fissh02 Would love some advice here!

I’m wondering if this will work for my bms the wiring is correct as I followed the diagram from bestech and now the bms wont turn on. I used my voltmeter to check and it runs 8.7 volts in its current condition but the e-switch wont do anything the battery by itself measures at 37.5 volts 10s5p. Seems the bms is my problem but dont know any fix for it I have emailed Lucy to see if they can replace it as I haven’t soldered anything to it just testing it

What model do you have? I am using the HCX-D52.

My guess is that you’ve got a faulty bms. Your wiring seems fine. What wire gauge are you using? Check for cold solder joints and the bms for shorts.

I thought so too but i just switched to the second BMS I got from Bestech and I’m still having the same issues. I am using 10 gauge pretty much everywhere.