Is there any proper documentation for the JK-BMS series?
The documentation about the LED’s on their website is basically junk. For example. My run LED on the inverter BMS is flashing. So are the SOC LEDs. Yet nothing in their documentation explains what it means.
All other states basically point you to the same explanation. Completely useless. There must be people here, other than Andy, that know exactly what the LED state really mean. Right?
The information above refers to manufactured battery packs with a supplied BMS.
Besides those, there are also companies selling seperate BMS-es intended to be used with self built lithium batteries. These are typically used when manufactured batteries with integrated BMSes don’t meet the requirement of the application, or to save costs.
SUPPORT WARNING: At Victron, we offer very limited support to systems running on these custom BMS batteries.
The following BMS systems are known to correctly follow the Victron battery specification (but are not tested by Victron!):
Just follow what the community has already discovered. There’s a ton of information online about how to build a battery with a JK BMS. IMO one of the best sources of information is the YouTube videos by Andy/Offgridgarage.
Despite being completely clumsy, I managed to build my DIY battery with the JK Inverter BMS and successfully integrate it into a Victron system. I studied many YouTube videos and websites, trying to distinguish the better ones from the worse ones. Yes, it’s more work to develop an understanding of the interrelationships than actually building the system. I was lucky, and my system worked perfectly right away—apart from the well-known weaknesses of the JK BMS with current measurement and the resulting SOC estimation.
I get that, but there are many people here using the JKBMS. And with great success. I’m new to JK. Used Dali before. But those others people should be resourceful.
Yeah. I know Andy and his vlogs from day one on YT. Thing is. There is. As far as I know. Still no good documentation. Simply explaining end users what is what. A YT video is way overboard for simple LEDs IMHO.
By the way. I learn fast. R&D person. Programmer. Editor of computer magazines back in the day.
But hey. Do you know what the blinking LEDs are telling me?
Edit: Tom. You are right The LEDs are indeed flashing when it charges the battery. Pretty obvious duh. Haha. What a fun this new BMS. Love it. Hate the failing documentation
I too use a Daly with my Victron and recently installed a JK BMS for my battery set. I funny think the Daly is that good at balancing.
Unfortunately I couldn’t get the JK to work and have just received a replacement. My initial mistake may have been the fact that I may have needed to turn the battery discharge switch to “on.” via the app.
How the hell was I supposed to know that.
When it was on though, it had more features and looked a much better BMS.
Yes, the JK BMS documentation kind of sucks. I had to rewrite the pin configuration when I went to install mine. I documented it here.
For JK BMS issues, you’re better off asking over at DIYSolarForum.com. If you have closed loop communication issues between a JK BMS and a Cerbo GX/Multiplus/Quattro ask there or here.
I chose to go open loop communication in my system. Too many flaky issues with closed loop that I didn’t want to wade through.
The JBD BMS’ that I used in my prior system (also open loop) were bulletproof and worked great. A user at the DIY forum wrote a whole new manual for that BMS and it’s published on the OverKillSolar.com site.
Yeah that is a good point. Thing is. I hoped that some of the German users here. YT folks using JK-BMS. Andy among others. Would see this and chime in. Well. At least I tried.
And nope. JK can’t read English or simply refuses to answer any of my emails. Anyway. What can I say. Guess see you on the other forum
The LEDs are indeed flashing when it charges the battery. Pretty obvious duh. Haha. What a fun this new BMS. Love it. Hate the failing documentation 
