JK BMS (4S, 200A) - did I brick it by that simple action (renaming and changing passwords)?

[SvenT]

Hey there,
today I received my JK BMS (JK-B2A8S20P-H).

I unpacked it and wanted to try the BT connection.
So I used a lab power supply, setted it to 12V and connected the "big" B- of the BMS and the B- of the sense port to GND and B+ and B4 of the sense port to the +12V.

The BMS started and I was able to connect via BT and the standard PW (1234) to the BMS.
I went through the pages and tried to change the number of cells to 4.
Okay although I entered 4 it changed to the value 2....hmmm
I then tried to change the capacity to 280Ah and agaibn the entered value was not taken but changed to 5Ah.

Well I thought "maybe is is confused as the sense wires for B1/2 and 3 are not connected.

So I just did basic stuff:
Changed the password to change the settings from the default 123456 to a number I really don´t forget.
App said it was successful.

I also tried to change the Bluetooth password also to a number I don´t forget - again the App stated it was successful.

The I wanted to chance the name of the BMS and the disaster came

I changed the Name to "BMS-Batt1"...
The App stated thyt I have to reconnect.....well......

The name in the App has only cryptic letters....nothing similar to "BMS-Batt1" and I cannot longer pair with it although I am absolutely sure, that I use the correct password.

Did I brick the BMS by that ?

Is there any chance of reactivating it by restoring factory defaults?

Any ideas?
The App had the version 4.9.0 (i installed it via Google Play Store on my Android phone - Samsung S21).
I then tried the newer version 4.9.1 (buld 64) but no success....

Any help is highly appreciated,
Oh I bought the BMS via AliExpress from Hankzor.

Maybe he is active in this Forum ?


Thanks for any hints and greets from germany
Sven

 

[rickst29]

Greetings back from USA.

I would have recommended that you avoid the change of ANY settings until the BMS has been connected to the actual pack, excluding just the Sense/Balance header. (It is Sense/Balance for the cells AND the power supply for the BMS itself, the BMS will not power up before connecting that header with sufficient "charging voltage" present).

Before connecting the header to the BMS, but with all battery cell leads connected, use a Volt Meter to verify that the pins on the header show increasing voltage (in the correct amount, in the correct order). This might be unnecessary, but I recommend that you pre-charge the pack to 13.6 Volts (3.4V per cell) before connecting BMS sense lead, assuring adequate BMS operating voltage.
- - -
I don't know if is wil remain unreachable (due to broken password), but it needs those individual cell wires present (with correct voltages) to accept correct cell count. Pull all power first. recommend correcting the cell count first (before change of password and battery name). name) your resset to dual ivudal cells

 

[SvenT]

Hey thanks for the reply,
I got into contact with Hankzor (the guy I bought it from).

What shall I say? Awesome support

He sent me a password hat was valid for 15 minutes to pair and another to access the settings.
After that I was able to login to the BMS, make the changes and all is fine,

It seems as if the mai problem was, that I only connected one cell.
Maybe the electronic uses individual cells for the necessary supplies on the BMS.
I asked Hankzor because if that was the problem it might be worth a note in the manual.

Or am I the only stupid guy who tries to du the initial startup with a lab power supply
Maybe the drawback of being an engineer

S.

 

[rickst29]

Yes, your initial startup (with effectively only the first and last cells connected) was a very bad idea. None of the software (microcode) was developed with that mis-configuration being supported, and you exposed some "issues" (to use an engineering term ) when you tried to use it that way.

Can you perhaps share the "15 minute mergency" password with @Steve_S and I using private messages? On this Board, he does most of the support with JK issues and assisted in writing the manual. I was the original tester of your specific model (the first with "heater support" function) and I also provide some support on these boards.

"Private Messages" (use the envelope icon) allows us to share information which may need to be shared with specific persons in the future, while not opening that information to the whole world.

 

[mhanna]

I just recently received and set up a JK-B2A8S20P-H.

I also was going to play with it and did think of only "powering" it up via 2 leads but did not ;-)
I actually did wait to set it up after I connect to it to my 4S battery arrangement.

Anyway, it is working great so far except that I did try to change its name and now I also only see garbled letters in the Bluetooth app.



I did not try to change the password so I can still get into the unit but every time I try to change the name to something else, I just get different garbled characters.

Does the new name have to be in quotes or start with a special character or such ? Any help would be appreciated.
I would be willing to do a reset, but the factory reset option seems to be removed from the menu.

Also Rickst29, you say you did some heater testing; I will need this option working soon, I can't find where I set the turn on-turn off temps for the heater, or is it static and could you share those values?

Thank you in advance.

Matt

 

[SvenT]

Yes, your initial startup (with effectively only the first and last cells connected) was a very bad idea. None of the software (microcode) was developed with that mis-configuration being supported, and you exposed some "issues" (to use an engineering term ) when you tried to use it that way.

Can you perhaps share the "15 minute mergency" password with @Steve_S and I using private messages? On this Board, he does most of the support with JK issues and assisted in writing the manual. I was the original tester of your specific model (the first with "heater support" function) and I also provide some support on these boards.

"Private Messages" (use the envelope icon) allows us to share information which may need to be shared with specific persons in the future, while not opening that information to the whole world.

Hey Rick,
well as my cells weren´t present in that moment I thought the lab supply does the job.
Maybe my descirption was in that point a bit misleading, but I used a 12V power supply and connected the +12V to B+ and B4 (so simulate the wholl pack).
The GND was connected to the B- (sense port and M6 thread).

Greets
Sven

 

[SvenT]

I just recently received and set up a JK-B2A8S20P-H.

I also was going to play with it and did think of only "powering" it up via 2 leads but did not ;-)
I actually did wait to set it up after I connect to it to my 4S battery arrangement.

Anyway, it is working great so far except that I did try to change its name and now I also only see garbled letters in the Bluetooth app.

View attachment 114503

I did not try to change the password so I can still get into the unit but every time I try to change the name to something else, I just get different garbled characters.

Does the new name have to be in quotes or start with a special character or such ? Any help would be appreciated.
I would be willing to do a reset, but the factory reset option seems to be removed from the menu.

Also Rickst29, you say you did some heater testing; I will need this option working soon, I can't find where I set the turn on-turn off temps for the heater, or is it static and could you share those values?

Thank you in advance.

Matt

Hm so I am not alone ;-)
Tha magic what it brought to operate was : Use all B- at GND and use B+ and B4 (In my planned 4S system) with the known result....

The garbled characters were exactly the same for me.
How do you power the BMS currently?

It seems as if it needs
- ALL + poles connected to the sense port
- B+ of the sense port connected to the + pole of the "TOP" cell
- B- of the sense port connected to the M6 threads AND the sense wires.

Maybe my assumption might be correct that the serveral internal supplies are generated from individual cells and maybe one supply (for the memory) is not properly up....but just a speculation.

Regards
Sven

 

[rickst29]

I just recently received and set up a JK-B2A8S20P-H.

I also was going to play with it and did think of only "powering" it up via 2 leads but did not ;-)
I actually did wait to set it up after I connect to it to my 4S battery arrangement.

Anyway, it is working great so far except that I did try to change its name and now I also only see garbled letters in the Bluetooth app.

View attachment 114503

I did not try to change the password so I can still get into the unit but every time I try to change the name to something else, I just get different garbled characters.

Does the new name have to be in quotes or start with a special character or such ? Any help would be appreciated.
I would be willing to do a reset, but the factory reset option seems to be removed from the menu.

Also Rickst29, you say you did some heater testing; I will need this option working soon, I can't find where I set the turn on-turn off temps for the heater, or is it static and could you share those values?

Thank you in advance.

Matt

You must correct the number of cells (from 8 to 4) before doing anything else. What is the total voltage of the battery pack?
If I recall correctly, you must avoid special characters in the "name", but spaces are OK within the middle of the alphanumeric text. I don't the exact text of my first try but it included a dash, something like "JK-200A BMS" (without the quotes, of course). It didn't work. I settled on "JK BMS 200A" *again without quotes) and that has been stable and responsive form several months after setting it, and through a couple of "it's my job to try it" unneeded shutdowns.

The heater function does not have independent parameters. (It would be nice if heat could be added BEFORE low temperature disables pack charging, bu that is not how it works.) It uses the low-temp charging cutoff to 'invoke' the start of start heating (i.e., it closes the grounding switch behind the heater's adapter cord plug-in, creating a full circuit). It uses the low-temp charge recovery value to stop heating, at the same moment it allows charging to resume.

I set my low-temp cutoff (Charge UTP) at 3 degrees, and my charge UTPR at 8 degrees (both being Celsius). You need to raise the UTPR value before UTP value - it will generate an error and refuse to adjust UTP if you try to set a value which equals or exceeds the already-present UTPR value.

When I received my JK, setting battery type to LFP (which should be done immediately after setting the correct number of cells) set a default value significantly below zero for Charge UTP - a value more appropriate for discharge, or for "regular" Lithium Ion cells. That default allowed for fatal charging below freezing. Some posts by @Steve_S imply that microcode "problem" to be fixed in newer shipments, but be sure to set it to good values for your battery pack environment.

More information from my initial testing: https://diysolarforum.com/threads/jk-4s-200a-bms.38623/post-520292, and actual use to run a higher-current heater configuration: https://diysolarforum.com/threads/bms-with-circuit-to-heat-the-batteries.40138/post-575086

 

[rickst29]

Hey Rick,
well as my cells weren´t present in that moment I thought the lab supply does the job.
Maybe my descirption was in that point a bit misleading, but I used a 12V power supply and connected the +12V to B+ and B4 (so simulate the wholl pack).
The GND was connected to the B- (sense port and M6 thread).

Greets
Sven

Greets right back! I understood your initial post, your English writing is very good. Thank you for clarifying for others. Activating with only the lab PSU was a bad idea, because it simulates only the entire pack - and not the 4 individual cells. Activating with no connection on the intermediate cells was likely a cause of at least some problems.

 

[mhanna]

I wired it up according to the manual, for 4S I have:

B- (black wire going to the negative post
B1-4 (sense wires) going to the cells 1-4
B5-8 not connected to anything (taped off)
B+ going to cell 4 (most positive)

Also, in your earlier post you mentioned that after you change values, such as # of cells or capacity the menu (via the app) and it did not show what you entered. Same for me, I entered 4 cells and as soon as I hit ok, the app showed 2. Same with battery capacity, change the value, the app shows wrong. It looks like the "refresh" is wrong, so now if I make a change to anything, I give is a few seconds after making the change, close the app then reopen, and then I can see the correct values that I entered.

I think I have a new SW spin; it needs some work.


There are also a few new options in the control area of the app that I can't find info on. I emailed JK support the other day for an updated manual or explanation but have not yet received a response.

Any idea what temp sensor shield, or GPS heart check is for?

And then in another thread on this forum the port labeled GPS was thought to be an actual rs-232, is the 'port switch' option for the GPS port or for the port labeled rs-485 ?




Thanks

 

[rickst29]

Your Sense/Balance wires are attached correctly. Most of the display contents which you picture seem to be new with your singificantly later S/W version (I have the same H/W version, but S/W at only 11.12). When I make changes, I must sometimes tap on the next field and wait a couple of seconds for the previous field to be updated.

I don't know what Temp Sensor Shield is. Do you have both temp sensors attached to cells within the pack?

 

[mhanna]

Thanks for replying so quickly,

I think one of the first things I did after powering up the BMS was to set the # of cells and the capacity. It was later that I tried giving it a new name.

I just tried right now to rename it again; it allows me to go through the steps:





After a new search:

 

[Steve_S]

@Steve_S and I using private messages? On this Board, he does most of the support with JK issues and assisted in writing the manual.

I have no association or relationship with HankZor or JiKong as such. I am JUST A USER of the JK-Bms and decided to edit & fix their poorly translated manual to proper English to help fellow DIY'ers. No different than the similar work I did with the Chargery BMS systems (okay that was a much bigger job). The original manual for JK was a terrible computer-translated mess and as a result, if anyone tried to translate that into their language, they ended up with useless gobbledegook. By cleaning up the English, the translator software(s) can do a much better job of it.

 

[mhanna]

Your Sense/Balance wires are attached correctly. Most of the display contents which you picture seem to be new with your singificantly later S/W version (I have the same H/W version, but S/W at only 11.12). When I make changes, I must sometimes tap on the next field and wait a couple of seconds for the previous field to be updated.

I don't know what Temp Sensor Shield is. Do you have both temp sensors attached to cells within the pack?

Yes, the 2 temp probes are attached to the batteries and seem to be reading correctly.

I also looked at the link you provided and read your review write-up, I did not see that before and thanks for doing it.

 

[mhanna]

I downloaded what I think is the latest manual from Git-hub, version 1.4 and it does not cover those newer options in the control area of the app, maybe it will be updated soon to tell us what they do, for now they stay off.

Thanks for describing how the heater function works, I do not wish to use that. I made the assumption that it worked the way we all want it to work with settings for on/off based on temps above freezing. I already have an external temperature monitor/controller that will start and stop the heating pads with my settings, was hoping to remove that extra device, wiring, probe, etc. oh well.

As far as the monitoring, reporting and cell balancing, it is doing that well.

The only outstanding issue now is to re-name the device in Bluetooth to something normal. As you can see above, I tried many times and it does not work, there has to be a hidden way to do a factory reset (hold down button for x seconds, etc.)

Any ideas?

My next thing to work on is to connect it to my Venus OS PI so I can read info beyond Bluetooth range.

Thanks

 

[SvenT]

Thanks for replying so quickly,

I think one of the first things I did after powering up the BMS was to set the # of cells and the capacity. It was later that I tried giving it a new name.

Hmm for me everything started to work properly after I connected all necessary connections.
Are you sure that the wiring is correct?
Could you check, whether the measured values of the 4 cells are plausible?

Maybe a Screenshot?

S.

 

[Delta Sierra]

I'm afraid I have the same problem with my jk BMS I just bought. I logged in successfully via Bluetooth but then changed my Bluetooth password to a new one.

This new one I changed it to doesn't work for some reason (even though I entered it twice in change screen to change it and it was accepted) maybe it has a max # of characters that I don't know about?

Does anyone know the best way to contact support? The contact form on their website doesn't work.

Is there a way to just reset everything back to default? Why do I need to contact support for a temporary password? Seems retarded, if I have physical access to the device I should be able to reset it.

 

[Delta Sierra]

I have since been able to contact Hankzor via aliexpress app and got a temp Bluetooth pin to login successfully.

they said there are bugs in recent app version and after I downloaded the suggested version 4.8.4, I am able to update all the passwords and it works great!

Link to that version (android): https://github.com/NEEY-electronic/JK/blob/JK-BMS/jkbms-4.8.4.132(1)(1).apk

 

[OffGridIdaho]

I have since been able to contact Hankzor via aliexpress app and got a temp Bluetooth pin to login successfully.

they said there are bugs in recent app version and after I downloaded the suggested version 4.8.4, I am able to update all the passwords and it works great!

Link to that version (android): https://github.com/NEEY-electronic/JK/blob/JK-BMS/jkbms-4.8.4.132(1)(1).apk

installed shows ver 4.2 not 4.4

 

[Saltyoldcruiser]

Yes, your initial startup (with effectively only the first and last cells connected) was a very bad idea. None of the software (microcode) was developed with that mis-configuration being supported, and you exposed some "issues" (to use an engineering term ) when you tried to use it that way.

Can you perhaps share the "15 minute mergency" password with @Steve_S and I using private messages? On this Board, he does most of the support with JK issues and assisted in writing the manual. I was the original tester of your specific model (the first with "heater support" function) and I also provide some support on these boards.

"Private Messages" (use the envelope icon) allows us to share information which may need to be shared with specific persons in the future, while not opening that information to the whole world.

If you still have that code and it's able to be shared I'd sure like to have it. I'm trying to get in touch with Hankzor myself and they have so far been unresponsive. I've lost my bluetooth password and need to reset it. This has been a nightmare and as much as I love the JK bms I'm pretty fed up with the lack of support.