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JiKong (JK) (Neey/Hankzor/HelTec/etc) Smart BMS with Active Balancer BT/Can/RS485 (Input Discussion pre-purchase)

Does the JK by chance do a pwm soft start ? Or is a precharge resistor appropriate?
 
Hello
I got mine a week or so ago.
The actual bms is very nice and working good.
I also bought the can bus module hoping to get it to communicate with my victron cerbo, that failed big time.
Doing a little research, i dont believe its true canbus??
I can confirm that it is transmitted something as my cerbo gx is receiving something
See pic
every bms has it own protocol running over the CANBUS. it won't work without writing a specific driver for venusOS.
 
Digging through the JKBMS material it appears these do not have a PreCharge Circuit within, which in my opinion is a bit LAME given that any lithium battery pack will have to cope with Inverters powering up and taking that start surge. So I asked them what do they suggest to solve it and why is such omitted from the design. Hopefully I will get an answer today.

JKBMS with Active Balancer --to-- PreCharge --to-- Inverter.
HOW have you dealt with it ? Push Button with Resistor ? Automatic somehow ? How do you deal with it when no one is around and Inverter Cycles (batt connect/disconnect etc) ?

IF you think that PreCharge should be added to JK, they can be contacted here : https://www.jkbms.com/contact/
https://www.jkbms.com/contact/
Unfortunately
This is not the official website of jkbms
You can view the logo shape on jkbms and the logo shape on the website. They are different,
 
@Nami Now that you have been on the forum a while, you will see there is a need for everyone to get the Exact Same Accurate information about the JK Product line. This is largely due to mixed information from different Vendors and out of date listings, as well as poor translations. I myself have been led on a Goose Chase for answers - which is holding up my own projects.

There is even a lack of clarity as to if an RS485 Module or CanBus Module is required or not and which LCD screen works or not.
Some of which you answered in this thread: https://diysolarforum.com/threads/jk-jikong-rs485-interface-wiring.35071/

IF you are indeed from JiKong then PLEASE do Introduce yourself and start the Thread with the Latest & Current up to date news & resources. If you would like input from our membership here on product improvements, ideas and dare I say Used Documentation, people here can be most helpful and we have done so before with other progressive manufacturers.

Thanks,
Steve
 
@Nami Ahora que ha estado en el foro por un tiempo, verá que es necesario que todos obtengan la misma información exacta sobre la línea de productos JK. Esto se debe en gran parte a la información mixta de diferentes proveedores y listados desactualizados, así como a traducciones deficientes. A mí mismo me han llevado a la búsqueda de respuestas en la Goose Chase, lo que está retrasando mis propios proyectos.

Incluso falta claridad sobre si se requiere o no un módulo RS485 o un módulo CanBus y qué pantalla LCD funciona o no.
Algunas de las cuales respondiste en este hilo: https://diysolarforum.com/threads/jk-jikong-rs485-interface-wiring.35071/

SI usted es de JiKong, POR FAVOR preséntese y comience el hilo con las noticias y los recursos más recientes y actualizados. Si desea obtener información de nuestros miembros aquí sobre mejoras de productos, ideas y me atrevo a decir Documentación usada, la gente aquí puede ser de gran ayuda y lo hemos hecho antes con otros fabricantes progresistas.

Gracias,
Steve
(y)
 
I ordered both the RS485 and CanBus modules. I was a little surprised that both units have 4 pin connectors, meaning both are meant to plug into the RS485 socket (but only one at a time).

My goal was to play with the CanBus interface. As a retired firmware engineer, I'm always looking for something to play with..... But I'm not really disappointed. I'll eventually research it, but I doubt that there is any data coming down the can interface, that is not also available on the straight RS485 interface....
Did you try to disassemble can unit? I don't have can unit but picture on ali say about CAN_H and CAN_L lines but no data on these lines. I found another pinout for can connector https://secondlifestorage.com/data/attachments/15/15578-aab950425e300cfd12eca41955395889.jpg but no vbat on my connector, i didn't try it. Is it possible connect CAN bus to bms without can converter?
 
Well @Nami has not returned to answer.

BOTTOM LINE - My JK Purchase = NIGHTMARE !

I got the BMS' but not the RS485 & CanBus modules...
NOW they "SAY" They being Mr Wang of JiKong in China that these modules are NOT Needed that you only need a Pigtail wire harness...
Then other contradictions pop up Here * on Vendor Sites ...
NAMI Showed Images that state these are optional ports / functions so how do we KNOW what we have... Ohhh there is no way to know THAT'S HOW.... The many mixed Postings by Many Vendors akso do not entirely JIVE and leave much to be desired for Information...

SADDEST PART OF THIS ! I asked Amy Wan of Luyuan to obtain the batch, with the required accessories and more bits, pieces etc needed to complete my final build and now 2 months of this KRAP I am finally PISSED OFF ! Amy tried her best and got Screwed by the idiots at JiKong !

I also have to get all New Butt-Splices, Terminal Ends because the wires are AWG the Splices & Terminals are Metric (AWG a bit bigger so Metric No Freakin Use) but at least she did send me the 4AWG Silicone Wire. Butt Splicing the Two 7AWG leads from B- & P- to a single 4-AWG Extension for the Ring Terminal extensions. ANOTHER PEEVE, 1/2 the BMS wires had the protective tips removed and so they are Frayed & must be cut back, which is a major PITA with teh ultray fine high capacity wire.

LESSON LEARNED: Find a Vendor who has everything in stock and that it is all compatible & serviceable and buy at one time from someone like HankZor. As for Help from/by JK Standard Issue KRAP ! Especially if they won't even post their presence as a Company & Rep here like others have done...

Possibly @upnorthandpersonal whose has been using these for ages can clarify if these RS485 & CanBus Modules are needed or not "now" or what the dealio is... I need to put the remaining packs together and am forced to get parts from Digikey (ouch $$$) cause I'm outta time piddling with this.


1644949781318.png
 
Possibly @upnorthandpersonal whose has been using these for ages can clarify if these RS485 & CanBus Modules are needed or not "now" or what the dealio is... I need to put the remaining packs together and am forced to get parts from Digikey (ouch $$$) cause I'm outta time piddling with this.

Ok, here is where the vendor communication issue comes from: RS-485 and CAN are provided by external modules. These modules convert the existing TTL/UART signal to these protocols. So vendors are correct: if you need RS-485 for example, you need the modules so that the TTL signal becomes an RS-485 signal. However, since most people want to connect these BMSs to their computer/R-Pi/what have you over USB, you don't need to go through those external modules first: you can just take the TTL signal and convert it to USB right away with a TTL to USB dongle.

This is by the way also why older RS-485 adapters don't work with newer BMSs: the baud rate changed, so the micro controller in the older adapter that is to hard coded to 9600Baud now can't work with newer versions of the BMS that run their ports at 115300Baud.
 
@Nami Now that you have been on the forum a while, you will see there is a need for everyone to get the Exact Same Accurate information about the JK Product line. This is largely due to mixed information from different Vendors and out of date listings, as well as poor translations. I myself have been led on a Goose Chase for answers - which is holding up my own projects.

There is even a lack of clarity as to if an RS485 Module or CanBus Module is required or not and which LCD screen works or not.
Some of which you answered in this thread: https://diysolarforum.com/threads/jk-jikong-rs485-interface-wiring.35071/

IF you are indeed from JiKong then PLEASE do Introduce yourself and start the Thread with the Latest & Current up to date news & resources. If you would like input from our membership here on product improvements, ideas and dare I say Used Documentation, people here can be most helpful and we have done so before with other progressive manufacturers.

Thanks,
Steve
Jkbms has three shapes,
The BMS of 60A and 80A (bd6a-17s / 20s / 24s-6p and bd6a-17s / 20s / 24s-8p) has only the default RS485 function and LCD interface,
BMS of 100A, 150A and 200A (bd-6a20s / 24s-10p and b1a-20s / 24s-10p and b2a-24s-15p and b2a-24s-20p) only has the default RS485 function and LCD interface,
Among them, b2a-24s-20p-can BMS has built-in can function,
There are two other BMS models of 200A, b2a-4s-20p (not yet produced) and b2a-8s-20p, which only have the default RS485 function and LCD interface,
If there are many needs, we will consider them
@Nami Now that you have been on the forum a while, you will see there is a need for everyone to get the Exact Same Accurate information about the JK Product line. This is largely due to mixed information from different Vendors and out of date listings, as well as poor translations. I myself have been led on a Goose Chase for answers - which is holding up my own projects.

There is even a lack of clarity as to if an RS485 Module or CanBus Module is required or not and which LCD screen works or not.
Some of which you answered in this thread: https://diysolarforum.com/threads/jk-jikong-rs485-interface-wiring.35071/

IF you are indeed from JiKong then PLEASE do Introduce yourself and start the Thread with the Latest & Current up to date news & resources. If you would like input from our membership here on product improvements, ideas and dare I say Used Documentation, people here can be most helpful and we have done so before with other progressive manufacturers.

Thanks,
Steve
 
We have cancelled the can module and built the can module into the b2a24s20p as a new model. B2a24s20p-can, this BMS is connected from the CANbus interface. Customers can extend and connect other devices according to their own needs,
 
Well @Nami has not returned to answer.

BOTTOM LINE - My JK Purchase = NIGHTMARE !
I got the BMS' but not the RS485 & CanBus modules...
NOW they "SAY" They being Mr Wang of JiKong in China that these modules are NOT Needed that you only need a Pigtail wire harness...
Then other contradictions pop up Here * on Vendor Sites ...
NAMI Showed Images that state these are optional ports / functions so how do we KNOW what we have... Ohhh there is no way to know THAT'S HOW.... The many mixed Postings by Many Vendors akso do not entirely JIVE and leave much to be desired for Information...

SADDEST PART OF THIS ! I asked Amy Wan of Luyuan to obtain the batch, with the required accessories and more bits, pieces etc needed to complete my final build and now 2 months of this KRAP I am finally PISSED OFF ! Amy tried her best and got Screwed by the idiots at JiKong !

I also have to get all New Butt-Splices, Terminal Ends because the wires are AWG the Splices & Terminals are Metric (AWG a bit bigger so Metric No Freakin Use) but at least she did send me the 4AWG Silicone Wire. Butt Splicing the Two 7AWG leads from B- & P- to a single 4-AWG Extension for the Ring Terminal extensions. ANOTHER PEEVE, 1/2 the BMS wires had the protective tips removed and so they are Frayed & must be cut back, which is a major PITA with teh ultray fine high capacity wire.

LESSON LEARNED: Find a Vendor who has everything in stock and that it is all compatible & serviceable and buy at one time from someone like HankZor. As for Help from/by JK Standard Issue KRAP ! Especially if they won't even post their presence as a Company & Rep here like others have done...

Possibly @upnorthandpersonal whose has been using these for ages can clarify if these RS485 & CanBus Modules are needed or not "now" or what the dealio is... I need to put the remaining packs together and am forced to get parts from Digikey (ouch $$$) cause I'm outta time piddling with this.


View attachment 83919
If there is a great demand in the future, we will also consider adding can function to b2a24s15p to become a new model b2a24s15p-can, which depends on the needs of customers
 
Ok, here is where the vendor communication issue comes from: RS-485 and CAN are provided by external modules. These modules convert the existing TTL/UART signal to these protocols. So vendors are correct: if you need RS-485 for example, you need the modules so that the TTL signal becomes an RS-485 signal. However, since most people want to connect these BMSs to their computer/R-Pi/what have you over USB, you don't need to go through those external modules first: you can just take the TTL signal and convert it to USB right away with a TTL to USB dongle.

This is by the way also why older RS-485 adapters don't work with newer BMSs: the baud rate changed, so the micro controller in the older adapter that is to hard coded to 9600Baud now can't work with newer versions of the BMS that run their ports at 115300Baud.
Check your BMS if the version is in V6 After X, his communication frequency is 115200baud,
If not, his communication frequency is 9600 baud
 
Check your BMS if the version is in V6 After X, his communication frequency is 115200baud,
If not, his communication frequency is 9600 baud

Yes, I know that. That's why the older RS485 module doesn't work with newer BMS versions. The micro controller in the old module expects 9600Baud.
 
Anyone have experience with the JK-B2A25S60P ?
Need the high peak current capability of a relay BMS, planning to charge and discharge a 16S LF280K pack several times a day with fairly high charge rates with my Quattro 48/140/10000VA. Due to the size of the charger/inverter, i need a precharge. Due to the high charge/discharge rates i think i need a active balancer.
This unit seems to tick all the boxes. From what i can see it has precharge, external relay support and a serial interface and driver for the Victron GX system ?
I do however have a couple of questions, are the relay/contactor outputs all fixed 12 V ? Based on the limited amount of documentation it seems like it ? If this is the case, this is an advantage as it seems like it is much cheaper/easier to get hold of EV200 with 12 V coil than 48 V coil. At least for the cheap ones on AliExpress (clones?).
Anyone know if the Venus serial driver is compatible with the JK-B2A25A60P or just the cheaper ones with internal switch ?

Perhaps the biggest question is with the precharge output, it say in the manual that this can be used for 12 V buzzer or precharge relay. I do not however find anywhere in the documentation where it say how to enable the precharge/buzzer ? Another question is what how long the precharge is in for and how long the delay between the precharge engangement and the main contator engagement ?
Another one is if the precharge output is capable of driving a large EV200 relay directly or if i only can use smaller mosfets or similar with this output.

Anyone that have any knowledge on this unit ? It does seem to be the swiss army knife that can do everything. It is the only BMS with relay and active balancing that i have found.
 
Anyone have experience with the JK-B2A25S60P ?
Need the high peak current capability of a relay BMS, planning to charge and discharge a 16S LF280K pack several times a day with fairly high charge rates with my Quattro 48/140/10000VA. Due to the size of the charger/inverter, i need a precharge. Due to the high charge/discharge rates i think i need a active balancer.
This unit seems to tick all the boxes. From what i can see it has precharge, external relay support and a serial interface and driver for the Victron GX system ?
I do however have a couple of questions, are the relay/contactor outputs all fixed 12 V ? Based on the limited amount of documentation it seems like it ? If this is the case, this is an advantage as it seems like it is much cheaper/easier to get hold of EV200 with 12 V coil than 48 V coil. At least for the cheap ones on AliExpress (clones?).
Anyone know if the Venus serial driver is compatible with the JK-B2A25A60P or just the cheaper ones with internal switch ?

Perhaps the biggest question is with the precharge output, it say in the manual that this can be used for 12 V buzzer or precharge relay. I do not however find anywhere in the documentation where it say how to enable the precharge/buzzer ? Another question is what how long the precharge is in for and how long the delay between the precharge engangement and the main contator engagement ?
Another one is if the precharge output is capable of driving a large EV200 relay directly or if i only can use smaller mosfets or similar with this output.

Anyone that have any knowledge on this unit ? It does seem to be the swiss army knife that can do everything. It is the only BMS with relay and active balancing that i have found.
I don't know the answer to other questions, but I wouldn't use an EV200 relay for the pre-charge circuit anyway. I'd limit the pre-charge with a suitable resistor and use a much cheaper relay in the pre-charge circuit.
 
I agree that it is completely unnecessary. I have some small 30 A SSRs i could use instead for this that i might use instead. The clone EV200's are however so cheap now that the price difference is not that big :O

With less than two watts of holding current on these as well, it seems like a no brainer compared to having 10-50 cheap mosfets in parallel like in most of the non relay based BMS systems. I would expect both internal resistance and reliability will be better on a mechanical contactor. Especially as long as you configure the inverter/charger to start/stop the charge/discharge.
 
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Hi, can someone please confirm the latest 200a continuous model number? I’m getting mixed info from some suppliers. I’m looking for the latest model with ‘can’port and that can connect to the JK touch screen. I’m lead to believe the model is B2a24s20p-can however one supplier advised it’s B2a24s20p and another B2a20s20p. A little confusing

I’m running 2 x 230ah 48v packs.

Cheers
 
I have a question about inverters connected to the JK BMS. If the JK shuts down for over or under voltage what happens with the inverter. Will there be a current spike when it comes back on?
 
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