Wiring new BMS

[Johnrobert999]

Replacing a BMS 13S, not sure how to wire it. The old one had more terminals.
This one only has 2 wires, blue and black. I'm assuming the black goes to the end of the battery with the last little black wire of the 14 and the red goes to the final positive of the battery also connects to the charger.

2 of the pictures came with BMS other is the actual BMS I took.

the link below is the battery I am working on.

Troubleshoot Battery

I just bought a $20, 6-year-old Panasonic battery. I checked with a multimeter, nothing on output, the charging cable input on the BMS I get 54 V I would like to check each cell group. The only battery I repaired before the batteries were at right angles to this one so it was a lot easier as I...

endless-sphere.com

 

[James340]

B goes to battery ground p is for discharge and c for charging. The 14 wires go in series. Starting with the black goes to the ground and first +is1 next is 2 working up to 13.You have to be very careful working on a battery. I would recommend watching some videos of BMS being installed. Ebike guy is entertaining

 

[Johnrobert999]

Thanks for the reply
My BMS only has 2 terminals, so I assume P and C share the same Blue wire.

 

[Nix Liou]

Thanks for the reply
My BMS only has 2 terminals, so I assume P and C share the same Blue wire.

Yes, the discharge - and charge - are connected (termed a common port BMS). The BMS sits inline with the negative terminal of the battery, with the B- terminal going to the battery negative, and the C-/P- terminal going to the discharge connector negative. Make sure you have all the balance wires labeled and connected properly. Usually it's best to connect the B- terminal before plugging in the balance connector, and before connecting the balance connector it should already be connected to each cell group. But I don't know that specific BMS brand or model.

 

[Johnrobert999]

The negative of the charger goes to the B- is that correct

 

[Nix Liou]

The negative of the charger goes to the B- is that correct

No, the B- terminal stands for battery minus and connects to the battery. The C- (or PC-) connects to the charge port, and the C stands for charge (or discharge).

 

[Johnrobert999]

Thanks for your patience
still not sure enclosed dia of old BMS and new.

As I understand, the positive charge and positive discharge go to the Blue, Negative discharge goes to the black not sure where the negative of the charger goes

 

[docw009]

1. Positive end of the cells, a red wire in the first picture, goes to the positive side of the discharge plug and the charge plugs,
2. The blue P- lead on the new BMS goes to the negative side of the dicharge and charge plugs,
3. The black B- wire on the new BMS goes to the negative end of the cells.

 

[Johnrobert999]

Thanks. It's easy when you know how.

I measured cell groups eaxh one 4.1v all about the same, so thats a good sign I think.
When fully charged, it goes up to only 53v I know its supposed to be 54, but maybe an older battery will not charge to 54
I will test it tomorrow if it stops raining see how long it lasts
I just built a new bike 1500w rear motor it goes like a rocket.

Tested it, not the greatest battery it did about 14 miles no pedaling on a very cold day better than expected for a $20 battery