Batt not charging - help!! (52V 14S 4P - JBD BMS - 14S 50A UART BT / JBD-SP14S004)

m0rg5

New Member
Region
Australia
Hey all,

I'm a noob that's been going through a hardcore learning curve around all this, what with the bad advice I got early on that led down a trail of confusion and mistakes.
As of today I've now rewired the balance wires a redonkulous amount of time times, has been quite some confusion and frustration, yet have got the 52v 14s 4p battery and bms registering all series' and voltages as it should.

I may well be becoming somewhat less of a noob as I pull more and more hair out on the long approach to bald ebike guru 🤷‍♂️ 🤞.

My setup:
- **Configuration**: 52V 14S 4P
- **Cells**: 56 total 18650 cells
- 43 saved from a damaged pack.
- 13 reclaimed cells (I ran full charge/discharge tests with a LiitoKala Lii-M4S, and ended up discarding about half of those).

**BMS Specs:**
- **Model**: JBD BMS 14S 50A UART BT (JBD-SP14S004)

For charger input have tested voltages, continuity, input, etc (at fuse holder that connects to C-) and everything seems in order.

The BMS seems to be working, showing all settings, can see it balancing and settings are editable via xiaoxiang and overkill bms apps (overkill so much clearer, without erroneous, double entries [multiple "cell num" entires, I'm looking at you], so based on OKB now. With some balance help I manually got all the cells all within .100mv (see img).

The 2 key things I need help with:

1. The BMS isn't allowing/showing any charge input. This could be due to my settings, that my cells were too far from each other, or something else - I'm charging with a 54.6 3a charger as I try to find the laptop power supply that i will canabilise/step-up to a 52v charger.

2. Any advice, gotchas, etc on my BMS battery settings (see img)?

Thanks in advance for any help you can offer!
 

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Cell voltages are looking good, No reason why it shouldn't charge. I'm not familiar with these JBS bluetooth BMS, although I have bought two and never used them. But now I have a android phone with no SIM that's doing nothing, so maybe I should try it,

How did you get it to balance if it doesn't charge? Did you set the balance voltage at 3.6V. Maybe you have to set it to 4.15-4.20 to get it to charge again? Probably some setup setting you have missed?
 
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