JK BMS Prep

jasgrif11

Hi All,

For those of you with the JK BMS, can you help answer the following (search doesn't seem to be working for me on Boards). I'm waiting for mine to arrive later this month.

1. Do you have to use the 4 small power cables on the BMS or can they be removed and attach your own from the battery directly into the BMS? If you have to use the existing cables, how are you joining them to the cables from your battery?
2. Does the JK support 35mmsq/6 ring lugs? I have 35mmsq cables
3. How are you wiring the JK to the battery (do both B- goto the most negative on the battery)?

Here is my current Seplos config, I'm looking to replace the Seplos.

Is anyone willing to share a few pictures of their setup?

Thanks

Big Lar

The two leads on the B- side are about 10sqmm(guess) cables each, I just connected them together with one lug and then bolted to the lug on the tail coming from the negative of the battery, much similar to the P- side and that's to the negative terminal of the inverter

poker--addict

switching my BMS.

Early JK BMS had the two cables coming from B- , new one I need to make the cables to attach to the lugs.

But do I need two or is one ok?

graememk

https://www.boards.ie/discussion/comment/122788062#Comment_122788062

Not really, but A bus bar across the two terminals would be ideal.

poker--addict

yes that would spread any load indeed. Will see if I have anything that would work as bus bar today.

SD_DRACULA

https://www.boards.ie/discussion/comment/122789669#Comment_122789669

Use one of the busbars you get with the cells and cut it in two or just use two cables instead.

Though probably not needed if it's the 100a version but I would do it for 150/200a versions.

poker--addict

any ideas what I am selecting here. Is it "user defined" on Solis 6kW inverter?

S'

You’ll have to use user defined on the Solis as the JK BMS doesn’t talk to the Solis inverter over CAN

graememk

https://www.boards.ie/discussion/comment/122790922#Comment_122790922

AoBo could possibly work.

And it does talk, the solis just doesn't want to listen! It will take the SoC % from the can in user defined.

poker--addict

remind me all, I think on other BMS I had V as the driver of cut on and off battery from invert.

I now have inverter showing % as per BMS.

I want to stop using battery at 20%, I saw this evening it continued below and then triggered the recharge which I think was set around 11% on the inverter

graememk

https://www.boards.ie/discussion/comment/122796311#Comment_122796311

It's discharge depth in the solis battery setting

poker--addict

ok. Will look at that again. Would have thought that would have caught it as it's set above.

also noticed in BMS if I change battery capacity from 199AH to 200AH, it really moves the percentage remaining battery by large amounts. Does that make sense? Cells are 200ah but figured reality of Chinese cells might be a bit lower. I did get a tool to size each cell one by one (runs a fan and measures power, but haven't the time/patience)

graememk

https://www.boards.ie/discussion/comment/122796410#Comment_122796410

Are you running just 16 or 32cells?

I don't know how the jk guesses the initial SoC but once your running you need to get it fully charged, voltage wise and then get it to reset to 100%

And yes I'd agree about the calb cells, possibly rate them around 180ah