Jk inverter bms settings

[J_Iu]

I need help on how to get the correct settings for my jk inverter bms with Growatt inverter to move the charging to 55.2v bulk charging and 53.6v float charging.
The inverter stopped charging when the battery voltage got to 3.32v as recorded by the bms.

 

[shvm]

Which JK BMS model is this ?
What you are asking for is charger/AIO settings and need to be configured on charger end, not the BMS.

 

[J_Iu]

Which JK BMS model is this ?
What you are asking for is charger/AIO settings and need to be configured on charger end, not the BMS.

It's Jk-PB2A16S20P.
Do you mean I should set the bulk and float charging on the inverter?
I was thinking whenever communication protocol is being used, it's only the bms that would send the command to the inverter, telling it the voltage to stop charging.
I was surprised when the inverter recording 100% at 3.32v and stopped charging while my settings on the bms was 3.35v float charging as shown in the screenshot.

 

[SomethingElse]

It's Jk-PB2A16S20P.
Do you mean I should set the bulk and float charging on the inverter?
I was thinking whenever communication protocol is being used, it's only the bms that would send the command to the inverter, telling it the voltage to stop charging.
I was surprised when the inverter recording 100% at 3.32v and stopped charging while my settings on the bms was 3.35v float charging as shown in the screenshot.

I am having the same issue. JK PB2A16S20 BMS sold in the docan diy kit. Balancing is set to start at 3.45 because everything Ive read says to have it there but the battery stops charging at 3.3V and reads 100%.. I never reach 3.45V. I measured all the voltages before assembling the battery but I am only now finding out I should have top balanced the batteries before the build. Some people say do a full cycle but others disagree saying wait for a few short cycles first to break the battery in. Amy at docan said it will communicate with the EG4 6000xp but Im still having a hard time getting everything to read after changing protocols, battery brands etc. I still cant find a definitive answer on how much max charge current should be!

It would be nice to create a "Everything you need to know, building, settings, and initializing 48v DIY battery" thread for newcomers. Since building one is almost half the cost of the EG4 indoor battery a lot of these types of threads will start popping up.

 

[kommando]

I am having the same issue. JK PB2A16S20 BMS sold in the docan diy kit. Balancing is set to start at 3.45 because everything Ive read says to have it there but the battery stops charging at 3.3V and reads 100%.

You probably need a Ghost battery (see link to thread) so your BMS never reports higher than 99%. Some inverters ignore the 100% and carry on charging until the target V is reached, others stop at 100% SOC which is wrong.

?

Thread 'JKBMS Inverter BMS SoC Fixer -- 'Ghost Battery' -- Open Hardware Project'

Aug 6, 2024

After dealing with the so called 100% SoC issue with the new JK Inverter BMS, I decided to take matters into my own hands and solve this issue once and for all.


Why might I need this?
1. You are using the new JK Inverter BMS (PB1A16S10P, PB2A16S10P, PB1A16S20P, PB2A16S20P)
2. You are using it in closed loop communication using CAN with a pylontech based protocol
3. You are using a chinese AIO inverter (Luxpower, EG4, Voltronic, Axpert, MPP, Growatt, Deye, SunSynk, Sol-Ark, the list goes on...)

• So far, the only exceptions that have been reported are Victron inverters (which...

• ....
• Replies: 80
• Forum: BMS (Battery Managment Systems)

• 
• 

 

[HRTKD]

I have that JK BMS. Due to the issues that have yet to be resolved by JK, I have chosen to not connect my inverter to the BMS. Maybe later, if they work it out.

 

[Steve_S]

As @HRTKD stated, at this time, it really is better to NOT use the Inverter to AIO Comms as there are many issues with it.
You can connect all the packs together in Parallel with the comms cables and monitor the packs in your bank as a whole with the PC App. The Phone Apps still only allow you to view 1 battery pack at a time and that is not likely to change either.

Currently, the most stable firmware for V15 Hardware is 15:27 and "apparently" newer fixed (actually fixed) firmware is coming. WAIT till others have tried it BTW, don't be an Alpha Tester.

I will provide JKBMS-Inverter Edition settings list below that uses common sense & conservative profile that work very well for everyone who has adopted it. Note that Balancing starts at 3.420V. I run a Bank of 7 Packs with these new 200A Inverter BMS, I am using TailCurrent/EndAmps at the Solar Controller/Shunt to transition from Bulk/Absorb to Float. EndAmps/TailCurrent is calculated as follows: 100AH X 0.05 = 5A TailCurrent. 280x0.05=14A TailCurrent.

SCC Settings: (Fairly Generic)

SETTING	V per cell	12V	24V	48V	notes
Bulk / Absorb: (boost)	3.437	13.74	27.5	55.0	Absorb Time < 60min Transitions to Float
Equalize:	0	NOT for Lithium Based Batteries
Float	3.425	13.70	27.4	54.8	allows cells to balance internally
Min Volts:	2.650	10.6	21.2	42.4	Never allow to drop too low. Safe Buffer
Max Volts:	3.575	14.3	28.6	57.2
Rebulk Voltage:	3.200	12.8	25.6	51.2
End Amps / Tail-Current:	formula: 100AH X 0.05 = 5A

(*1): End Amps is calculated: (100AH X 0.05 = 5A or 280AH X 0.05 = 14A.
EndAmps = TailCurrent
Coulumbic Efficiency / Battery Status Meter Efficiency for LFP = 99%.
This gets the bank charged to full with high amps (Constant Current Constant Voltage) and then float (Constant Voltage, Variable Current) tops off so the cells are at 3.437Vpc. I
! Do Not forget to adjust for Voltage Offsets between Actual Voltage @ Battery Terminal & at Solar Controller.

BMS With Active Balancing should be set to start Active Balancing at 3.420V or possibly lower to 3.410 so that the cells can balance out at the top and not affect the charging process.

Very Special NOTE: Floating & Saturating to 3.437vpc, accounts for the Voltage Settling post Charge of any kind which actually brings the cells to just below 3.400Vpc.

JKBMS - Inverter Edition Config Settings: Notes along the side.




FILL IN

FILL IN


Default = 10mv, 5mv OK with matched cells.

User the VOLTAGE @ Pack Terminals with NO in/out draw (no wires) but breakers on.

If Calibrated above with 0A them leave alone.





Start too low and slows process.



Could be 1A pending on BMS Model
































Depends on BMS model








Depends on BMS model







VERIFY TEMP SETTING onwards
These are based on Real LFP limits





























This changes relative to switch settings

 

[HRTKD]

Is there a way to switch the JK BMS to °F instead of °C? I looked earlier today and nothing was obvious.

 

[J_Iu]

As @HRTKD stated, at this time, it really is better to NOT use the Inverter to AIO Comms as there are many issues with it.
You can connect all the packs together in Parallel with the comms cables and monitor the packs in your bank as a whole with the PC App. The Phone Apps still only allow you to view 1 battery pack at a time and that is not likely to change either.

Currently, the most stable firmware for V15 Hardware is 15:27 and "apparently" newer fixed (actually fixed) firmware is coming. WAIT till others have tried it BTW, don't be an Alpha Tester.

I will provide JKBMS-Inverter Edition settings list below that uses common sense & conservative profile that work very well for everyone who has adopted it. Note that Balancing starts at 3.420V. I run a Bank of 7 Packs with these new 200A Inverter BMS, I am using TailCurrent/EndAmps at the Solar Controller/Shunt to transition from Bulk/Absorb to Float. EndAmps/TailCurrent is calculated as follows: 100AH X 0.05 = 5A TailCurrent. 280x0.05=14A TailCurrent.

SCC Settings: (Fairly Generic)

SETTING	V per cell	12V	24V	48V	notes
Bulk / Absorb: (boost)	3.437	13.74	27.5	55.0	Absorb Time < 60min Transitions to Float
Equalize:	0	NOT for Lithium Based Batteries
Float	3.425	13.70	27.4	54.8	allows cells to balance internally
Min Volts:	2.650	10.6	21.2	42.4	Never allow to drop too low. Safe Buffer
Max Volts:	3.575	14.3	28.6	57.2
Rebulk Voltage:	3.200	12.8	25.6	51.2
End Amps / Tail-Current:	formula: 100AH X 0.05 = 5A

(*1): End Amps is calculated: (100AH X 0.05 = 5A or 280AH X 0.05 = 14A.
EndAmps = TailCurrent
Coulumbic Efficiency / Battery Status Meter Efficiency for LFP = 99%.
This gets the bank charged to full with high amps (Constant Current Constant Voltage) and then float (Constant Voltage, Variable Current) tops off so the cells are at 3.437Vpc. I
! Do Not forget to adjust for Voltage Offsets between Actual Voltage @ Battery Terminal & at Solar Controller.

BMS With Active Balancing should be set to start Active Balancing at 3.420V or possibly lower to 3.410 so that the cells can balance out at the top and not affect the charging process.

Very Special NOTE: Floating & Saturating to 3.437vpc, accounts for the Voltage Settling post Charge of any kind which actually brings the cells to just below 3.400Vpc.

JKBMS - Inverter Edition Config Settings: Notes along the side.
View attachment 250877



FILL IN

FILL IN


Default = 10mv, 5mv OK with matched cells.

User the VOLTAGE @ Pack Terminals with NO in/out draw (no wires) but breakers on.

If Calibrated above with 0A them leave alone.





Start too low and slows process.



Could be 1A pending on BMS Model
































Depends on BMS model








Depends on BMS model







VERIFY TEMP SETTING onwards
These are based on Real LFP limits





























This changes relative to switch settings

Let me try your settings and report back.

 

[Steve_S]

Is there a way to switch the JK BMS to °F instead of °C? I looked earlier today and nothing was obvious.

No there isn't a way to change C to F. F only applies to a very few places, unlike English in general.

 

[J_Iu]

As @HRTKD stated, at this time, it really is better to NOT use the Inverter to AIO Comms as there are many issues with it.
You can connect all the packs together in Parallel with the comms cables and monitor the packs in your bank as a whole with the PC App. The Phone Apps still only allow you to view 1 battery pack at a time and that is not likely to change either.

Currently, the most stable firmware for V15 Hardware is 15:27 and "apparently" newer fixed (actually fixed) firmware is coming. WAIT till others have tried it BTW, don't be an Alpha Tester.

I will provide JKBMS-Inverter Edition settings list below that uses common sense & conservative profile that work very well for everyone who has adopted it. Note that Balancing starts at 3.420V. I run a Bank of 7 Packs with these new 200A Inverter BMS, I am using TailCurrent/EndAmps at the Solar Controller/Shunt to transition from Bulk/Absorb to Float. EndAmps/TailCurrent is calculated as follows: 100AH X 0.05 = 5A TailCurrent. 280x0.05=14A TailCurrent.

SCC Settings: (Fairly Generic)

SETTING	V per cell	12V	24V	48V	notes
Bulk / Absorb: (boost)	3.437	13.74	27.5	55.0	Absorb Time < 60min Transitions to Float
Equalize:	0	NOT for Lithium Based Batteries
Float	3.425	13.70	27.4	54.8	allows cells to balance internally
Min Volts:	2.650	10.6	21.2	42.4	Never allow to drop too low. Safe Buffer
Max Volts:	3.575	14.3	28.6	57.2
Rebulk Voltage:	3.200	12.8	25.6	51.2
End Amps / Tail-Current:	formula: 100AH X 0.05 = 5A

(*1): End Amps is calculated: (100AH X 0.05 = 5A or 280AH X 0.05 = 14A.
EndAmps = TailCurrent
Coulumbic Efficiency / Battery Status Meter Efficiency for LFP = 99%.
This gets the bank charged to full with high amps (Constant Current Constant Voltage) and then float (Constant Voltage, Variable Current) tops off so the cells are at 3.437Vpc. I
! Do Not forget to adjust for Voltage Offsets between Actual Voltage @ Battery Terminal & at Solar Controller.

BMS With Active Balancing should be set to start Active Balancing at 3.420V or possibly lower to 3.410 so that the cells can balance out at the top and not affect the charging process.

Very Special NOTE: Floating & Saturating to 3.437vpc, accounts for the Voltage Settling post Charge of any kind which actually brings the cells to just below 3.400Vpc.

JKBMS - Inverter Edition Config Settings: Notes along the side.
View attachment 250877



FILL IN

FILL IN


Default = 10mv, 5mv OK with matched cells.

User the VOLTAGE @ Pack Terminals with NO in/out draw (no wires) but breakers on.

If Calibrated above with 0A them leave alone.





Start too low and slows process.



Could be 1A pending on BMS Model
































Depends on BMS model








Depends on BMS model







VERIFY TEMP SETTING onwards
These are based on Real LFP limits





























This changes relative to switch settings

Cell OVP and RCV sending failed

 

[SomethingElse]

Cell OVP and RCV sending failed

I received this message a lot. I'm not sure what order it has to be done in, but after changing Everything I could I went back and started changing things it wouldn't let me.

 

[J_Iu]

I received this message a lot. I'm not sure what order it has to be done in, but after changing Everything I could I went back and started changing things it wouldn't let me.

I think the settings between OVP, RCV, SOC 100% and OVPR are done in sequence. Otherwise the sending will fail.
I can remember the sequence.
I just hope Steve's settings will work

 

[TechRider]

I used Andy's settings and they're pretty close to what Steve Posted. I think I need to change the Start Balance voltage. I'm going to have to review...

 

[Steve_S]

Yeah, the sequence of entering the values is a terrible issue... raised so many times with JK and Nothing.
Now if using the PC-App you can use the TAB key and it takes you through the right sequence but bouncing up & down.
Also, just because the value you set might still show after the error is displayed, does not mean it took it. After you have everything set, go back, starting at the bottom clicking OK for every field (YUP it is a PITA) but I've had to do that with the phone app far too many times. Doing the settings with the PC App is better... IF only the darn thing could use a stored profile to update batches of BMS... another simple issue ot addressed.

 

[J_Iu]

I'm using phone app for the settings. I will keep trying

Yeah, the sequence of entering the values is a terrible issue... raised so many times with JK and Nothing.
Now if using the PC-App you can use the TAB key and it takes you through the right sequence but bouncing up & down.
Also, just because the value you set might still show after the error is displayed, does not mean it took it. After you have everything set, go back, starting at the bottom clicking OK for every field (YUP it is a PITA) but I've had to do that with the phone app far too many times. Doing the settings with the PC App is better... IF only the darn thing could use a stored profile to update batches of BMS... another simple issue ot addressed.

 

[J_Iu]

I used Andy's settings and they're pretty close to what Steve Posted. I think I need to change the Start Balance voltage. I'm going to have to review...

I will like to have the Andy's video.
If I can get 3.40v (54.4) as bulk charging and 3.35v (53.6) as float charging, I will be happy.
At the moment, the charging only stop at 3.31v (52.9) and my Growatt record 100%

 

[Glock24]

Yeah, the sequence of entering the values is a terrible issue... raised so many times with JK and Nothing.
Now if using the PC-App you can use the TAB key and it takes you through the right sequence but bouncing up & down.
Also, just because the value you set might still show after the error is displayed, does not mean it took it. After you have everything set, go back, starting at the bottom clicking OK for every field (YUP it is a PITA) but I've had to do that with the phone app far too many times. Doing the settings with the PC App is better... IF only the darn thing could use a stored profile to update batches of BMS... another simple issue ot addressed.

If only there was a proper manual that explained how it must be done it would not be a problem.

 

[J_Iu]

In another thread, some people are using ghost battery kits to push the charging to the end because the coulomb counter of the JK PB2A16S20P has caused the charging to stop prematurely.
Going for these kits should be my last option. Let me still try other options available......

 

[AshleyL]

In another thread, some people are using ghost battery kits to push the charging to the end because the coulomb counter of the JK PB2A16S20P has caused the charging to stop prematurely.
Going for these kits should be my last option. Let me still try other options available......

Nope, there is no other option.
Using USE mode has its own charging issue as well where the inverter will only rebulk charge if it detects voltage drop of 1.5v less than float voltage. From how flat lifepo4 voltage is between 5% to 95%, you can guess where this is going.

 

[J_Iu]

I used Andy's settings and they're pretty close to what Steve Posted. I think I need to change the Start Balance voltage. I'm going to have to review...

Can I see the Andy's settings?

 

[TechRider]

For the ghost battery, it fixes the issue where the comms with the inverter cause the charging to stop early. (It's kind of a hacky workaround but it works.)

Here's the spreadsheet for Andy's settings that I did back in May. I'm not sure if they've been updated since or not.

Ug, first paste was ugly, here's a screenshot:

 

[J_Iu]

For the ghost battery, it fixes the issue where the comms with the inverter cause the charging to stop early. (It's kind of a hacky workaround but it works.)

Here's the spreadsheet for Andy's settings that I did back in May. I'm not sure if they've been updated since or not.

Ug, first paste was ugly, here's a screenshot:
View attachment 251985

Thanks Sir

 

[muzzamil]

As @HRTKD stated, at this time, it really is better to NOT use the Inverter to AIO Comms as there are many issues with it.
You can connect all the packs together in Parallel with the comms cables and monitor the packs in your bank as a whole with the PC App. The Phone Apps still only allow you to view 1 battery pack at a time and that is not likely to change either.

Currently, the most stable firmware for V15 Hardware is 15:27 and "apparently" newer fixed (actually fixed) firmware is coming. WAIT till others have tried it BTW, don't be an Alpha Tester.

I will provide JKBMS-Inverter Edition settings list below that uses common sense & conservative profile that work very well for everyone who has adopted it. Note that Balancing starts at 3.420V. I run a Bank of 7 Packs with these new 200A Inverter BMS, I am using TailCurrent/EndAmps at the Solar Controller/Shunt to transition from Bulk/Absorb to Float. EndAmps/TailCurrent is calculated as follows: 100AH X 0.05 = 5A TailCurrent. 280x0.05=14A TailCurrent.

SCC Settings: (Fairly Generic)

SETTING	V per cell	12V	24V	48V	notes
Bulk / Absorb: (boost)	3.437	13.74	27.5	55.0	Absorb Time < 60min Transitions to Float
Equalize:	0	NOT for Lithium Based Batteries
Float	3.425	13.70	27.4	54.8	allows cells to balance internally
Min Volts:	2.650	10.6	21.2	42.4	Never allow to drop too low. Safe Buffer
Max Volts:	3.575	14.3	28.6	57.2
Rebulk Voltage:	3.200	12.8	25.6	51.2
End Amps / Tail-Current:	formula: 100AH X 0.05 = 5A

(*1): End Amps is calculated: (100AH X 0.05 = 5A or 280AH X 0.05 = 14A.
EndAmps = TailCurrent
Coulumbic Efficiency / Battery Status Meter Efficiency for LFP = 99%.
This gets the bank charged to full with high amps (Constant Current Constant Voltage) and then float (Constant Voltage, Variable Current) tops off so the cells are at 3.437Vpc. I
! Do Not forget to adjust for Voltage Offsets between Actual Voltage @ Battery Terminal & at Solar Controller.

BMS With Active Balancing should be set to start Active Balancing at 3.420V or possibly lower to 3.410 so that the cells can balance out at the top and not affect the charging process.

Very Special NOTE: Floating & Saturating to 3.437vpc, accounts for the Voltage Settling post Charge of any kind which actually brings the cells to just below 3.400Vpc.

JKBMS - Inverter Edition Config Settings: Notes along the side.
View attachment 250877



FILL IN

FILL IN


Default = 10mv, 5mv OK with matched cells.

User the VOLTAGE @ Pack Terminals with NO in/out draw (no wires) but breakers on.

If Calibrated above with 0A them leave alone.





Start too low and slows process.



Could be 1A pending on BMS Model
































Depends on BMS model








Depends on BMS model







VERIFY TEMP SETTING onwards
These are based on Real LFP limits

 

[muzzamil]

Hey man can you check my jk bms parameters setting i have catl 280ah 16 cell 48v
Model JK_PB1A16S10P kindly guide me this setting is right or not
This changes relative to switch settings