Hankzor JK-BMS B2A24S20P 70 A charge -> and watch the video

[clauberty]

Worked fine for 6 months on a 8s LiFePO4 with a DC-DC Converter, battery connected to and UPS
Charging with max 5A and discharging with no more then 25
Now i managed to install and connect all my Victron solar gears
Victron MULTIPLUS-II 48/5000/70-50 GX
Victron Energy SmartSolar MPPT 250/100 VE.Can
Victron Energy Lynx Power In
and added JK-BMS B2A24S20P on the 16 x 304ah 3.2v prismatic lifepo4 battery cell

All was fine until one day the sun God decided to show his power Charge limit in the BMS is set to 100A and the charge controller can do 100A so charging was done at 75A read with clamp meter

All OK but when it come to stop charging because of cell OVP reached please watch video and please give me 2-5min from your preciouses time write your opinion.

Yes seller cannot see where is the problem .....

So this happen on Friday and Monday was/is a holyday, so on Thursday when i would return to work (60km from my home) my 16 cells would look like 16 elephant's and imagine the place if would they catch file or exploded due to overcharge

Failed miserably, and if we check the advertising of the product "Never crash -> independent watchdog design " watchdog is sleeping in my case.

well yes i did reset (disconnect and discharge voltage), install the lattes APP set to default by pressing the liFePo4 button,

well now that I'm writing what I done the reset switch is what i did not used,

but let me have my doubts that this will change the situation... any way on Thursday will be done

 

[sunshine_eggo]

It's not respecting the OVPR value and repeatedly cycling the charge protect on and off.

What BMS did you have before the JK?

 

[clauberty]

and do not care abut the charge on/off switch state, charge switch is set to of and still repeatedly switch charge on off and on

my first BMS is this JK and all 16 cells are new

and i have 2nd jk an 8s now for the UPS

 

[perryg114]

So what is the exact problem. It looks like it cut the charge because of one cell going high. Is that not what it supposed to do?

 

[clauberty]

So what is the exact problem. It looks like it cut the charge because of one cell going high. Is that not what it supposed to do?

well beside that charge is switched ON/OFF almost each second and if you "watch" the clip this is done with charge function set to OFF then i hope you see the problem

and charging with 10->15 A one sec and discharging with same amp next sec and outside is full sunshine is not the right behavior

how does your bms is behaving when the value from the cell over voltage is reached? does switch off charging?

if i set cell over voltage to 3.55 and cell over voltage release to 3.3 -> charge should not be switched ON until one off the cell is at or under 3.3V

is it true or false?

 

[RV10flyer]

I guess you'll have to do like the rest of us with these junk cells from China. Set your charge voltage to 55.2 V. Your BMS is the back up system to shut things down. Your solar charge controller is primary.

 

[Clifton]

On my JK, I have my max set to 3.6v . I use these settings as a safety, not a charge feature. I set my inverter to 55.6 max charge and never have to use the JK safety settings. I have had things set too close in amp charge discharge and charged them and all is good.

I would raise your max to 3.6 and set your inverter to only charge to just below your max set in the JK.

 

[clauberty]

what app you are using with this bms

i use ENJpower because first time i scan the QR code from bms page would not load so i search JK BMS and i find this

https://www.jkbms.com/support/ and if you click on google play or Apple Store app will download

after install app connection to BMS was and is ok

but in Andy video is see he use the app with cloud, i managed to download

Chengdu Jikong Technology Co., Ltd| Lithium battery active equalization protection board | lithium battery equalizer Tel: 18628129012

成都极空科技是一家专注于动力电池管理系统研发的企业，作为“锂电池主动均衡技术的领导者”。极空是行业内首家开发，并批量应用主动均衡技术的公司。双向主动均衡技术，实时调整电池组容量差异，可有效延长续航里程及使用寿命，突破电池单体流放电一致的瓶颈。详询：17784306842

www.jk-bms.com

it but it would not connect to bms

and you can see that at V 4.8.4 cloud upp version -> fix device switching issue, i do not know but it sound like my problem

how do i make the cloud icon app to work with BMS?

 

[Steve_S]

The most current APP off the PGYER: (Use Translate from Simplified Chinese to English) It is not posted to the Github yet.

极空BMS

点击下载安装，尽享便捷电池管理！ 极空BMS最新版是一款智能电池管理系统，为您提供全方位的电池管理服务。 主要特点： - 实时参数显示：通过手机连接电池，您可以随时查看电池的参数，了解电池的状态和健康状况。 - 主动均衡器设置：通过软件，您可以设置主动均衡器的参数，确保电池的均衡性，延长电池寿命

www.pgyer.com

The Latest Manual:

JK/JKBMS INSTRUCTION.pdf at JK-BMS · NEEY-electronic/JK

Contribute to NEEY-electronic/JK development by creating an account on GitHub.

github.com

NOTE: There are some Default Settings in the JKBMS for LFP which are outright wrong (been corrected in the newest editions)
Have a look at the "Advanced Settings" image in this thread for the BMS, the Charge Profile there is for a Midnite Classic SCC But others are pretty similar, this works beautifully as you will see in that thread.

Steve_S-Tech: My Final Config for Midnite Classic SCC & JKBMS' w/ Large Bank (works amazingly well) Includes Charge Profile & BMS Config

INTRO: I have debated posting this for a while until I got everything tweaked in and working as best as possible. The End Result is Gobsmackingly Good ! I cannot speak for other SCC and such as each is different & unique in their own ways BUT this may likely be a Good Reference. Civility &...

diysolarforum.com

Good Luck, Hope it helps.

 

[clauberty]

well i read user manual so many times that i can reproduce it for an exam

i have a felling that BMS cannot switch off charging wen charging current is over a certain value of amps 10 -> 15 -> 20 A, i do not know

i will test this hope in the near future

reason i say this is because this BMS worked well on a 24V UPS where i put 8 cells (with DC-DC converter to reach the minimum V for the BMS)

and UPS charge current is not more than 3->5A

 

[rhino]

Can you show pic of your BMS and wiring connecting it to the battery?

 

[clauberty]

Hello

i have some problems my setup

Victron MULTIPLUS-II 48/5000/70-50 GX -> grid is connected no feed in is set and ext. current sensor connected
Victron Energy SmartSolar MPPT 250/100 VE.Can, connected to inverter by ve.direct
Victron Energy Lynx Power In as a buss bar
Victron Smartshunt 500A/50mV connected to MPPT via bluethooth
8x Sharp NU-JD540
JK-BMS B2A24S20P {not connected to inv via CAN} on the 16 x 304ah 3.2v prismatic lifepo4 new battery cells


1. When inverter is set to "inverter only" the displayed load is 300W and more -> Grid inv inv only.jpg

but when inverter is set to "ON" the displayed load is 150W ->200W -> Grid inv ON.jpg

All this with the same load no load added or removed, write this to not get answer like you added or removed load!!!

Q -> what is the reason for different load displayed when inv is set to Inverter only or ON?

2. Regarding MMPT settings, ext control is displayed in VM, and different V in Victron connect and remote VM

in remote console MMPT -> Networked Operation charge voltage is set 60.8 but in the MMP via Bluetooth voltage is set to 55V

Q -> what is the reason for different V
Q -> is there a way to fully control MMP from VM remote console like from Bluetooth APP ?
Q -> what is the reason "ext control" is displayed? what device is controlling the MMPT?
Q -> in MMPT absorption is set to 55.2 and batt voltage is still rising, why?

3. In the VM no matter what state of charge battery have, displayed value do not go under 90% even when inv was disconnected due to low battery

4 unfortunately JK BMS do not working as it should and do not turn off charging when one cell reach the set "over voltage value" which is 3.55

ess config is attached

 

[clauberty]

Can you show pic of your BMS and wiring connecting it to the battery?

each nut is tightened to specified torque, tool picture is attached

 

[clauberty]

reason i say this is because this BMS worked well on a 24V UPS where i put 8 cells (with DC-DC converter to reach the minimum V for the BMS)

and UPS charge current is not more than 3->5A

Tis 8s bms is working has expected when one cell is over the set OVP charge is off

the 24S black BMS worked the same way when it was on the UPS in 8S config with DC-DC converter to get the min V of the BMS to turn ON

in attachment is the 8s BMS and charge is off when cell OVP is reached,

yes it is a picture but i will make a video to see that it remained off until OVP release v is reached

imagine what would happen with the batteries if charge will not stay OFF

 

[clauberty]

Your BMS is the back up system to shut things down.

Tis is the problem -> the BMS do not shut down / stop charging when cell OVP is reached

 

[Clifton]

Your bms is working fine, it went form charge to not charging and showed a positive amp charge to a negative back to a positive. The BMS is a safety. If you want 3.5v per cell, set your inverter to charge at 3.5x16=56v and bms over volt to 3.55 to 3.6. One cell will always be a little higher than the rest. You need a little buffer in your settings.

 

[clauberty]

what do you say, settings are ok in MPPT?

problem is this, one cell will always charge faster -> will reach the OVP, when this is the case BMS must turn charge OFF if cannot keep cell voltage under the set OVP with balance current.

not ON one sec and OFF next second and so one, my opinion

let say MPPT go crazy, what is the job of the BMS? to stop charging!! to not boil the cells

why the 8S BMS stay OFF with charge fiction? you can see in the picture is written with yellow!!

and that is a UPS, can you set that UPS to stop charging or to lower the V because one cell is at OVP? NO you cannot

reason is that UPS is set for acid battery and there is trickle charging, if BMS would not stop charging battery material would be all over the place

you can see BMS have 22 days in use

 

[Clifton]

. You are charging to 55.2v, 3.45 per cell but one cell takes a charge slower so the voltage is higher and you trip the bms. Set your bms ovp a little higher, at least 3.6v . It's a safety. It is working, you are just making it work hard. Try it then see how it goes.

 

[hwse]

well i read user manual so many times that i can reproduce it for an exam

i have a felling that BMS cannot switch off charging wen charging current is over a certain value of amps 10 -> 15 -> 20 A, i do not know

i will test this hope in the near future

reason i say this is because this BMS worked well on a 24V UPS where i put 8 cells (with DC-DC converter to reach the minimum V for the BMS)

and UPS charge current is not more than 3->5A

On my 4s verson, when I reach OVP it stops charging and stays off until the lowest cell drops below OVPR. I can also shut off charging manually with the app. Mine is on a sailboat and primary charging is done by an engine powered alternator. On the last cruise, I had my drive belt start to shred on me while crossing a major shipping channel with lots of current and rocky out cropping's. I needed to keep motoring with what was left of the belt, but it would not survive the 60A load of the alternator. I turned off charging and the alternator went to 1A output to the start battery and 0A to the LFP. The JK stopped 60A+ of charge and stayed off for the next 3 hours until I got back to port.
I am not sure why yours does not do this and have never seen mine behave as seen in your video.

 

[clauberty]

. You are charging to 55.2v, 3.45 per cell but one cell takes a charge slower so the voltage is higher and you trip the bms. Set your bms ovp a little higher, at least 3.6v . It's a safety. It is working, you are just making it work hard. Try it then see how it goes.

i will copy what i write on youtube here to have info and continuity

Gilbert Viloria​

11 hours ago
Keep you bms over voltage protection at 3.65 and set your charge controller at 56v which is 3.5 per cell..

Sorry but i consider this wrong way of thinking, why? at 3.65 cell is at MAX V so going over the 3.65 even with 0.01v -> is damage to cell, small or little; or has little as possible it is still damage to the cell so from here you cut cycle count and capacity. Is it worth it? not on my money, because at the end all comes to money.

Yes, setting your charge controller at 56v which is 3.5 per cell is the solution to keep this BMS and the system in working order,

Yes, the MPPT was controlled by ESS and in config of the ESS i disable charger but charge values in the charger settings are still taken in consideration (Victron software BUG) and values are set to 56.8 so 56.8/16=3.55 meaning 0.5v over the cell OVP in the BMS. ESS now removed and voltage in MPPT is 55.2/16=3.45 my settings and MPPT now respect the set voltage and stop charging and switch to float mode all ok.

From this i conclude that the BMS it cannot stop the charging when the charge voltage is higher with 0.8V than the set voltage !!!! 3.5*16=56 so 56.8-56=0.8v -> REALLY ??? at 0.8v is unable to switch off charging????

Then what to expect at 25 or 50 v more....

Than make the following scenario MPPT get damaged in the way that will provide voltage over the set value in BMS cell OVP is set to 3.55. With the behavior you can see in the clip the cells will be over charged and JK BMS will not stop to charge and JK will not pay for the brand new cells...

And to not write an "essay" on this problem, (because i could) what is the reason you use a BMS? -> To protect the cells from over or under voltage and over current charge or discharge is it true or not?

What is the advertising of any BMS on the market -> will protect from bla bla bla ..... JK is with bigger balls saying that have a hardware watchdog!!! REALLY ???

Well i can say that in this case the watchdog is sleeping in his corner if it exist !!!

More problems,

i do not know ho copy ho but there are two type of JK BMS, or at least APP version

App version 4.8.1.128 https://www.jkbms.com/support/ https://www.jkbms.com/wp-content/uploads/2022/08/enjpower-bms-4.8.1.128-21.zip

the secon is the aliexpress or alibaba JK BMS that will send you the link to download the app and yes i buy this one

how i discovered this? well seller do not responded and i of course start to search the web and found https://www.jkbms.com/support/ , downloaded the app and hit the problem described above, then i write to seller and what a surprise -> you have the wrong application was the feedback from seller; Ou Ou Ou really? (of course not the app is the problem for the hardware behavior of the BMS but anyway) is that so??

Than what is the right App for the BMS?

App version 4.9.3 (build 69) https://www.pgyer.com/Cfq3?spm=a2g0s.imconversation.0.0.77743e5fs6R12a So from the info above draw your conclusion and please let me know it, thank you