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Configuring JK BMS (for LFP Battery Cells)

The default settings on a JK Inverter BMS (JK-PB Series) are not good for connecting to your Victron Inverter / Charger.

You will run into errors like: “High cell voltage alarm”.

Note: These settings are for LiFePO4 (LFP) battery cells.

Basic Settings

Name Description Default Value Suggested Value
Cell Count Number of cells connected in series 16 Your actual cell count
Battery Capacity (Ah) Nominal battery capacity used by the BMS for SOC calculation 100 Your actual capacity
Balance Trigger Voltage Minimum cell-voltage difference before balancing starts 0.010 V 0.010 V
Start Balance Voltage Cell voltage above which active balancing can start 3.300 V 3.400 V
Max Balance Current Maximum active balancing current 2.0 A 2.0 A

Advanced Settings

Name Description Default Value Suggested Value
Cell OVP Cell Over Voltage Protection; disconnects charging if a cell exceeds this voltage 3.650 V 3.600 V
Voltage Cell RCV Requested Charge Voltage; BMS asks the charger/inverter for this voltage per cell 3.500 V 3.450 V
SOC-100% Voltage Cell voltage used as the threshold for resetting SOC to 100% 3.475 V 3.449 V
Cell OVPR Voltage below which an OVP fault can recover 3.450 V 3.448 V
Cell UVPR Voltage above which an undervoltage fault can recover 3.100 V 2.650 V
SOC-0% Voltage Cell voltage below which SOC is reset to 0% 3.000 V 2.640 V
Cell UVP Cell Under Voltage Protection; disconnects load if a cell falls below this 2.800 V 2.600 V
Power Off Voltage Cell voltage at which the BMS shuts down completely 2.500 V 2.500 V
Voltage Cell RFV Requested Float Voltage after the battery reaches 100% 3.400 V 3.350 V
Name Description Default Value Suggested Value
Voltage Smart Sleep Cell voltage associated with Smart Sleep 3.500 V 3.285 V
Time Smart Sleep Time condition for Smart Sleep 24 h 24 h
Continued Charge Current Maximum continuous charging current; BMS reports ~95% of this to the charger 100 A 105 A
Charge OCP Delay Time an excessive charging current is tolerated before protection activates 3 s 5 s
Charge OCPR Time Time charging remains disabled after an overcurrent event 60 s 60 s
Continued Discharge Current Maximum continuous discharge current; BMS reports ~95% of this to inverter 100 A 100 A
Discharge OCP Delay Time an excessive discharge current is tolerated 10 s 300 s
Discharge OCPR Time Time discharge remains disabled after overcurrent protection 60 s 60 s
Charge OTP Over-temperature protection for charging 50 °C 50 °C
Charge OTPR Temperature at which charging is allowed again 45 °C 45 °C
Discharge OTP Over-temperature protection for discharging 50 °C 50 °C
Discharge OTPR Temperature at which discharging is allowed again 45 °C 45 °C
Charge UTP Under-temperature protection for charging 10 °C 2 °C
Charge UTPR Temperature at which charging is allowed again 12 °C 5 °C
MOS OTP MOSFET over-temperature protection 80 °C 80 °C
MOS OTPR MOSFET temperature required for recovery 70 °C 70 °C
SCP Delay Short-circuit protection delay 1500 µs 1500 µs
SCPR Time Recovery delay after short-circuit protection 30 s 5 s
Device Address Address used for communication / parallel BMS configuration 0 1
Data Stored Period Interval for storing internal data 3600 s 864000 s
RCV Time Time the BMS maintains RCV voltage before switching to float 0.5 h 1.0 h
RFV Time Time the BMS remains at float voltage before requesting RCV again 12 h 6.0 h
Emergency Time Duration for emergency operation below UVP 30 min 30 min
User Private Data User-defined identification text JK-BMS put Userdata
User Data 2 Additional user-defined data JK-BMS put Userdata
UART1 Protocol Protocol used on UART1 0 0
UART2 Protocol Protocol used on UART2 0 1
CAN Protocol CAN communication protocol 0 4
LCD Buzzer Trigger Condition that activates the buzzer 1 1
LCD Buzzer Trigger Value Value at which buzzer activates 20 20
LCD Buzzer Release Value Value at which buzzer stops 25 25
DRY1 Trigger Trigger condition for dry-contact relay 1 0 4
DRY1 Trigger Value Trigger value for relay 1 0 3600
DRY1 Release Value Release value for relay 1 0 3550
DRY2 Trigger Trigger condition for dry-contact relay 2 0 0
DRY2 Trigger Value Trigger value for relay 2 0 45
DRY2 Release Value Release value for relay 2 0 40
Con. Wire Resistance Continuous-wire resistance compensation 0.00 mΩ 0.00 mΩ

This post is under construction.

Factory defaults can vary between JK-PB hardware/firmware versions. Values marked as defaults should therefore be treated as indicative unless verified on a factory-reset BMS of the relevant firmware version.

See also this website: https://off-grid-garage.com/my-settings/