Overkill BMS wiring

[Offgridreefer]

I'm wiring up 4 of these 48v 16s overkill bms, the diagram isn't consistent with any of the bms wiring videos I've seen on YouTube, including the one by Will Prowse wiring up the 8s version of this exact bms. The diagram clearly shows connecting the first lead to first cell negative, then the second to first cell positive, and the third to second cell positive. Then ot gets weird. The 4th goes to 4th cell negative, 5th to 4th cell positive, 6th to 6th cell negative and 7th to 6th cell positive. It continues connecting to the positive and negative of every other cell through the rest of the battery. Every time I've seen a bms wired, all the leads go to the positive of every cell, except the first which goes to the first cell negative. Is the diagram wrong, or is this bms different?

 

[acdoctor]

This is from their website they also have that picture.

 

[Offgridreefer]

This is from their website they also have that picture.

Based off of that it appears one lead goes to every busbar connecting each cell, not connected to either terminal, negative or positive, directly.

 

[mikefitz]

Is the diagram wrong, or is this bms different?

A little confusig but the buss bar links the positive cell terminal to the next cell negative so connecting the BMS lead at either end of the buss bar will detect the same voltage.
Being consistent with the connections would be more ideal as depending on current flow and buss bar properties there could be a small volt drop across the buss bar.

Mike

 

[740GLE]

Black being pack negative terminal and red being pack positive terminal is all that matters.

Them calling the lead numbers in “reverse” seems more semantic than anything.

 

[HRTKD]

A little confusig but the buss bar links the positive cell terminal to the next cell negative so connecting the BMS lead at either end of the buss bar will detect the same voltage.
Being consistent with the connections would be more ideal as depending on current flow and buss bar properties there could be a small volt drop across the buss bar.

Mike

Exactly. I've had a plan to upgrade my "free" cell terminal bus bars with some DIY bus bars that are more stout. Instead of putting the balance lead on the cell terminal stud I'm going to drill a hole in the bus bar and tap the hole so the balance lead can go there.

 

[Offgridreefer]

Great, thanks!