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JK BMS received

Diesel Pro

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Received my JK BMS today. I ordered the 8S 2A 200A BT based on what I saw online. The Hankzor store showed the black case unit with 2 pair of cables off each side. What I received was a silver box and no cables JK-B2A8S20P. It is the correct unit and apparently I missed the pictures showing the unit. I had planned to join the twin cables in a single 2ga terminal, but now I need to rethink this and order more stuff apparently. Need to find some nice flexible cable and how to attach? I have a butane torch that I can use to solder. I wasn't really planning on soldering though.
 

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I think that's the model I'm about to order and the terminal holes should be threaded.
 
They look like they are threaded, but maybe 2 threads? That little dainty 6mm thread is not exceptionally strong. I wonder if I can just run one 2ga cable and be done with it?

Looking for a good accurate wiring diagram and instructions for activating the bluetooth if anyone has them.
 
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I managed to get it powered up and found the device in search but went to connect and says device not recognized.
 
They look like they are threaded, but maybe 2 threads? That little dainty 6mm thread is not exceptionally strong. I wonder if I can just run one 2ga cable and be done with it?

Looking for a good accurate wiring diagram and instructions for activating the bluetooth if anyone has them.
I think you need to upgrade the app itself to latest version. Did you click the QR code in the manual or how did you find it?

Threads are good on the BMS. I bolted a copper bus bar to mine to hang the unit off the side of the battery. I also have the shunt bolted to the other side. Works great
 
I think you need to upgrade the app itself to latest version. Did you click the QR code in the manual or how did you find it?

Threads are good on the BMS. I bolted a copper bus bar to mine to hang the unit off the side of the battery. I also have the shunt bolted to the other side. Works great
Could you post a photo? I am planning to use the 8S 2A 200A BT for a 2P4S 280Ah pack for my boat with a fixed 12v/24v boost converter.
 
I think you need to upgrade the app itself to latest version. Did you click the QR code in the manual or how did you find it?

Threads are good on the BMS. I bolted a copper bus bar to mine to hang the unit off the side of the battery. I also have the shunt bolted to the other side. Works great

Updated here: https://diysolarforum.com/threads/jk-bms-bt-error-device-is-not-supported.33514/

The bus bar thing makes great sense. Not sure about adding a Shunt though? I guess it serves a purpose, but the BMS is supposed to have all that info available so why add more connections is the way that I look at it.
 
Received my JK BMS today. I ordered the 8S 2A 200A BT based on what I saw online. The Hankzor store showed the black case unit with 2 pair of cables off each side. What I received was a silver box and no cables JK-B2A8S20P. It is the correct unit and apparently I missed the pictures showing the unit. I had planned to join the twin cables in a single 2ga terminal, but now I need to rethink this and order more stuff apparently. Need to find some nice flexible cable and how to attach? I have a butane torch that I can use to solder. I wasn't really planning on soldering though.
I was also kind of expecting the black casing.
Seems to be the 24S model that got that black casing with ready soldered wires ? Next time.

I really like the functionality of the app. All kind of adjustments etc. and for that reason I would go for JK on my next build.

External shunt?
I would like to have the current flow in my Victron app. And for that reason I am going for a Victron shunt also in my build.
 
Could you post a photo? I am planning to use the 8S 2A 200A BT for a 2P4S 280Ah pack for my boat with a fixed 12v/24v boost converter.
IMG_20220107_155238.jpg

My battery. EVE 280LFK series.
-I am compressing with 2 plastic cutting boards and 6 rods. I have used some old wire sheath to insulate the rods from the cells.
-I just bought some copper bar and cut/drilled/bent as necessary. So it comes off the terminal at a 90 and bolts directly to the BMS. Then at the bottom of the BMS I used a small piece of bar to connect the shunt directly to it as well.

I use an AiLi/TR16 battery monitor. The JK has a Coulomb counter but I can't get it to match the BM. Ie. I have tried cycling the battery from full to empty and back to calibrate them and although they match at the bottom end, by the time they are full it's off (right now my batteries are at 95% according to the JK but only 83% according to the BM. (The SOC of 26.8v would imply somewhere in the middle)
 
View attachment 78678

My battery. EVE 280LFK series.
-I am compressing with 2 plastic cutting boards and 6 rods. I have used some old wire sheath to insulate the rods from the cells.
-I just bought some copper bar and cut/drilled/bent as necessary. So it comes off the terminal at a 90 and bolts directly to the BMS. Then at the bottom of the BMS I used a small piece of bar to connect the shunt directly to it as well.

I use an AiLi/TR16 battery monitor. The JK has a Coulomb counter but I can't get it to match the BM. Ie. I have tried cycling the battery from full to empty and back to calibrate them and although they match at the bottom end, by the time they are full it's off (right now my batteries are at 95% according to the JK but only 83% according to the BM. (The SOC of 26.8v would imply somewhere in the middle)
I don’t think the shunt body should contact the heat shield on the BMS…
 
I like it! I configured mine in block form as well, but I put the bars on so that my main terminals were 90° from where yours ended up basically at the gap between each 4 cell group.. Now I am kicking myself because I ordered flexible busbars and will end up needing another short one (51.5mm) if I change my connection configuration. The configuration pictured would fit my box with the BMS mounted to a busbar. I currently have mine set up on my bench busbar mounted for my discharge/charge cycle test, but pretty sure it will not fit my box this way. I may just use the solid busbars for the two that connect cells end to end.
 
View attachment 78678

My battery. EVE 280LFK series.
-I am compressing with 2 plastic cutting boards and 6 rods. I have used some old wire sheath to insulate the rods from the cells.
-I just bought some copper bar and cut/drilled/bent as necessary. So it comes off the terminal at a 90 and bolts directly to the BMS. Then at the bottom of the BMS I used a small piece of bar to connect the shunt directly to it as well.

I use an AiLi/TR16 battery monitor. The JK has a Coulomb counter but I can't get it to match the BM. Ie. I have tried cycling the battery from full to empty and back to calibrate them and although they match at the bottom end, by the time they are full it's off (right now my batteries are at 95% according to the JK but only 83% according to the BM. (The SOC of 26.8v would imply somewhere in the middle)
This is a very nice setup right there
 
I got an 8s 200A JK BMS that looks exactly like this as well. My question is about the balance leads. There are 10 balance leads that came with the connector which has me a little confused. I connected the black (negative) to the main negative terminal of the battery, then 1 red positive to each of the corresponding positive terminals on the batteries. I checked at the connector that the voltage went up by about 3v per lead and that all checked out. But what do I do with the last red lead that isn't connected? the 8th red lead reads the correct 25v (my batteries aren't fully charged). Then the last lead isn't connected to anything. What did you guys do?
 
The last two wires both go to 8+
 

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Received my JK BMS today. I ordered the 8S 2A 200A BT based on what I saw online. The Hankzor store showed the black case unit with 2 pair of cables off each side. What I received was a silver box and no cables JK-B2A8S20P. It is the correct unit and apparently I missed the pictures showing the unit. I had planned to join the twin cables in a single 2ga terminal, but now I need to rethink this and order more stuff apparently. Need to find some nice flexible cable and how to attach? I have a butane torch that I can use to solder. I wasn't really planning on soldering though.
FWIW, I ordered the BMS "package" with the LCD included from Hankzor.

Having now received it, I can confirm that in addition to the LCD, this package includes the 7AWG power cables, bolts, balance cables, and temperature probes.
 
View attachment 78678

My battery. EVE 280LFK series.
-I am compressing with 2 plastic cutting boards and 6 rods. I have used some old wire sheath to insulate the rods from the cells.
-I just bought some copper bar and cut/drilled/bent as necessary. So it comes off the terminal at a 90 and bolts directly to the BMS. Then at the bottom of the BMS I used a small piece of bar to connect the shunt directly to it as well.

I use an AiLi/TR16 battery monitor. The JK has a Coulomb counter but I can't get it to match the BM. Ie. I have tried cycling the battery from full to empty and back to calibrate them and although they match at the bottom end, by the time they are full it's off (right now my batteries are at 95% according to the JK but only 83% according to the BM. (The SOC of 26.8v would imply somewhere in the middle)
Hey @BigBrosMo I have been studying your setup to understand the connection because am looking forward to have a similar set-up however I cant trace the origin of the black wires especially at the middle they seem to be emerging from the bottom of the batteries, could you snap a more clear shot of your set up and send it to privately. ? The red ones are okay so would like to understand the black ones and would appreciate more photos and insights , your setup is quite neat and k have it for reference purposes .
 
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