Hi, I need some assistance. I am retrofitting a Pace BMS into a 15S battery. PBMS Tools connects fine and allows me to change the BMS from 16S to 15S but nobodoy can tell me what to do with the extra balance cable to clear the error from having no Cell attached.

@RexxV, unfortunately I don't know the Pace BMS.

Most BMS manuals like the JBD BMS supporting 7S to 21S indicates how to connect different cell configurations. Normally you would connect the unused balance wires to the last or second last cell. 

Here is an example diagram for the JBD BMS:

Hope you find a solution. 

Blessings, Deon 

Sorry for the thread necro, I've also picked up a Pace BMS that was configured for 16 cells. I can't find anywhere in PbmsTools (V2.5 and V3.0.1) to set it for 15 cells. I have entered the password 123456 which allows many other settings to be changed but can't find the setting to change the number of cells. Can someone please point me in the right direction? Thanks!

Have you tried connecting the last two wires together? the 15th wire and 16th wire to the 15th cell

my 15s battery has two thin red  wires on the last cell

 

Is there a local supplier for the Pace BMS?

where did you get yours?

8 minutes ago, Deondti said:

Have you tried connecting the last two wires together? the 15th wire and 16th wire to the 15th cell

my 15s battery has two thin red  wires on the last cell

 

Is there a local supplier for the Pace BMS?

where did you get yours?

This seems how it works on some other BMS. The last wire is the end of the series string giving the total DC voltage of the pack. 

On 2024/07/24 at 8:40 AM, Deondti said:

Have you tried connecting the last two wires together? the 15th wire and 16th wire to the 15th cell

my 15s battery has two thin red  wires on the last cell

 

Is there a local supplier for the Pace BMS?

where did you get yours?

I managed to find the settings in PbmsTools 2.5 to change the numbers of cells, It's under "System Config" and then "Cell Number Setting" You have to type in the number of cells you have and then click "Setting" in order it to save the number.

When I changed the BMS settings from 16 cells to 15 cells, the BMS no longer monitored cell 14, (was expecting it to no longer monitor cell 16) but continued monitoring cell 15 and 16. I had to move the wire from cell 15 to the cell 16 input on the BMS and the wire from cell 14 to the cell 15 input on the BMS. The cell 14 input on the BMS is now no longer connected to any cells. Now on the BMS display, it has a dash - next to cell 16 instead of 0V and the low cell fault has disappeared.

I'm not sure if there's a local supplier of Pace BMSs, I got mine on Facebook Marketplace, the seller had a 52V 100Ah battery that had a few cells fail. He kept the cells and sold me the empty box and BMS.

Edited July 25, 20241 yr by Orcish75