• Have you tried out dark mode?! Scroll to the bottom of any page to find a sun or moon icon to turn dark mode on or off!

diy solar

diy solar

JKBMS Inverter Edition Problems/Issues | No Support / Help to fix major issues. - DO NOT BUY ! Warning (as of Oct.12.2024)

When wiring the bms balance/cell leads is cell 1 where the main positive is for the battery or the main negative that goes to the bms?
You may find this thread useful.
This one caught Off-Grid Garage Andy by surprise.
So don't worry about asking questions, not everything makes sense and others will share their mistakes, so you don't have to do it the hard way.
edit: added YT link
 
Last edited:
Can someone help me understand why this battery won't take any more charge, ths is one and one other, the other 4 batteries which are close in voltage (a bit higher now) are taking ~40-60 amps but this one stopped around this voltage, all have latest firmware and are hooked in parallel.

PXL_20250207_234912226.jpg
 
The other four batteries have the exact same settings?

Based on the Ah capacity, there's less than 4Ah left to put into it.
yeah, they all have same settings, this is a slave battery, all the batteries in are parallel. The ah are off, that is why I want them to get fully charged so it will reset it to get the SOC to be more accurate (it has been awhile since they have been able to get fully charged.)
 
Sometimes things equalize when everything is resting. Especially if in parallel
 
yeah, they all have same settings, this is a slave battery, all the batteries in are parallel. The ah are off, that is why I want them to get fully charged so it will reset it to get the SOC to be more accurate (it has been awhile since they have been able to get fully charged.)

Disconnect the communications and see what happens.
 
Hey guys I need to update four packs to 15.38 as they are all on random versions like 15.24/26 and one of the packs has very poor soc % accuracy (the .26 one I think)
What's the process to fix if one of them fails/bricks while doing the update so I'm ready if it happens.
 
Hey guys I need to update four packs to 15.38 as they are all on random versions like 15.24/26 and one of the packs has very poor soc % accuracy (the .26 one I think)
What's the process to fix if one of them fails/bricks while doing the update so I'm ready if it happens.
Go watch Andy from offgridgarage at youtube. All the baby step to adult steps are available there.
 
I'll throw my hat in the ring here. I built 4 batteries last April/May and the BMS's were running 15.17 I added 2 more around July that were running 15.24. I was mostly satisfied with how they were operating but I started to feel that I wasn't getting the capacity that I should. I realized some of my settings weren't optimal so I did as much looking as I could find for a good set of settings. Thursday I updated the settings and over the weekend I upgraded.

Results:
- All 6 Upgraded without issue (prior to that I had to reload one of them at least 3 or 4 times but I think it was my crappy RS485 adapter, I used a new one this time.) Went to 15.38
- 2 of them lost their settings completely, all voltages changed and my cycle count went to 0.
- 4 of them reported their SOC ~ 10% when it was showing around 60% before
- 2 of them reported ~50% SOC

Living in OH, we haven't had a lot of sun and had a nice amount of freezing rain on Sat after I was finished. Today we got a decent amount of sun (66kWh) so I was able to get a decent charge on them but still not a full 100% charge yet. I don't believe I've ever gotten a true balance charge on them so I'm excited to see how things go once I can get them fully charged. I've considered throwing some grid power at them but I'm not really looking to raise my electric bill right now.
 
anyone here with solis can confirm if compatible and what protocol are using ?
 
Solis user here.
Set CAN protocol to Pylontech at the JKBMS, but do not select Pylontech at the Solis Inverter, instead, you must select "Lithium Battery LV".
You've had the hard (sometimes painful) journey of figuring out what works and how.
But I am wondering, what Firmware Version you are using and on how many packs (bank config please).

----
Just did a quick scoot around to see if anything new has popped up on JK Firmware etc.. Seems even Andy gave up in his garage and moved on...
Not terribly surprised, I guess he "finally figured out" they were just using him too.
 
You've had the hard (sometimes painful) journey of figuring out what works and how.
But I am wondering, what Firmware Version you are using and on how many packs (bank config please).

----
Just did a quick scoot around to see if anything new has popped up on JK Firmware etc.. Seems even Andy gave up in his garage and moved on...
Not terribly surprised, I guess he "finally figured out" they were just using him too.
15.38 on all three EVE packs (280ah + 280ah + 314ah) for the main Solis inverter S6-EH1P12K03-NV-YD-L.
Solis inverter reports continuous warning if I set Pylontech protocol at the inverter. Setting it to "Lithium Battery LV" will make the warning disappear and BMS-Inverter communication works normally. Reason being Solis inverter looks for PYLON tag in the communication protocol for validation and JK doesn't implement the PYLON tag for its BMS Pylontech protocol. Still have to set the JKBMS CAN protocol to Pylontech for "Lithium Battery LV" to work.

Older V14 with 14.26 on my Growatt SPF 3000, 5000ES & 6000ES. The measurement shunt on both v14 and v15 are whacky as usual, at least with the latest 99% 'holding' algorithm, the battery packs are properly charged now.

On both v14 and v15 with latest firmware, I am not sure on why those dry contact work few times then it stops working randomly, next it starts to work again. Dry contact hardware failure perhaps?

Aside of JKBMS, I have disastrous experience with NEEY/ENERKEY active balancers too. Eight out of ten units of 10A active balancers gone bonkers close to one year of usage. So much for buying extra for spares.
For what it worth, JKBMS active balancer function are still working normally.
 
Fine fine......
Using Growatt SPF 3000, 5000 and 6000 ES.
Have both V14 and V15 hardware with latest firmware available (v14.20 and v15.27)
Tried Pylontech and Growatt protocol on JKBMS, no luck with SOC100% stop charging.
*Growatt inverter only support Pylontech and Growatt own protocol*

Critical issue with JKBMS coulomb counting, it doesn't take account of voltaic and coulombic efficiency during charge and discharge cycle.
It will always take more power to re-charge a discharged battery.

From what I can see, JKBMS actually expects 100% efficiency in charge and discharge cycle, duh.......assuming if the 100% is not triggered by single cell voltage, the coulomb counter gonna trigger 100% without actually fully charging the battery.
Example, after discharging a 280ah battery pack by 200ah, it requires 201ah or 205ah to fully recharge the pack again.

Charging and discharging several times in a day gonna cause the SOC % to drift negatively for certain.
Good point.
I also observed that it drifts more on cloudy days, when on 'only Solar charging', and noticed on the Growatt app that 20W are drawn from the battery when house is on grid and no sunshine, and 0 Amps reported by the JK BMS app. This probably means the digital bit depth 'granulation' of minimum amp reading of the BMS is > 0.38A (20W/52V = 0.38A), and this can't be fixed by FW updates, as it's a hardware design thing.
 
Last edited:
15.38 is available in Andy's google drive link, FYI. I've been running it for around 6 weeks. No issues.
Just updated a JK PB (200amp/2amp) from FW 15.21(as received) to 15.38. Just connected a power supply to the Bat+ and B- to power up unit to update FW (no batteries connected). I have been doing the configuration setups on units I have this way before connecting them to batteries.

After I updated FW to v15.38 it runs fine for 60 seconds then shuts itself down.

Pushing the button again and it runs for another 60 seconds.

Hopefully this is something related to not having batteries connected, like if battery undervoltage which it would be if no batteries connected. Previous version FW would stay on when run from power supply without batteries.

Looked at settings and only 60 second timer setting was for over current recovery time to reset overcurrent alarm which would not shutdown unit.
 
Solis user here.
Set CAN protocol to Pylontech at the JKBMS, but do not select Pylontech at the Solis Inverter, instead, you must select "Lithium Battery LV".
with that protocol i got alarm when max with big panels power, jk says the protocol to use with solis is same of Deye anyone confirm ?
 
with that protocol i got alarm when max with big panels power, jk says the protocol to use with solis is same of Deye anyone confirm ?
You sure you read it right?
Set the Pylontech protocol at JKBMS.
Set the "Lithium Battery LV" at Solis inverter.
 
i have tested that and if you have many power from panels when get 100% you will get alarm and need restart invertrr then to discharge...
on these particulary model S5-EH1P5K-L, on the S6-EH1P8K-L-PLUS not get same issue and yes is work fine with pylon protocol
 
i have tested that and if you have many power from panels when get 100% you will get alarm and need restart invertrr then to discharge...
on these particulary model S5-EH1P5K-L, on the S6-EH1P8K-L-PLUS not get same issue and yes is work fine with pylon protocol
I am using S6-EH1P12K03-NV-YD-L

This is weird, what kind of alarm you get at Solis inverter side? Do cross check with the JKBMS log as well.
 

diy solar

diy solar
Back
Top