Distribution
JK BMS JK-B2A8S30P 300 A wiring diagram
300 A common-port BMS for 12/24 V banks with 2 A active balancing and Bluetooth. V19.0.1 supports 3–8S LiFePO4/Li-ion and 7–8S LTO. B− connects to pack negative; P− to chargers and loads. Cell taps, B+ supply and sensors are not drawn. Configure the −20°C factory charge cutoff for the cells; CAN, RS485 and heating are optional.
- Compatible systems
- 12 V / 24 V
Wiring diagram
How the B2A8S30P 300A is wired.
Open this example in Crimp to use your own parts and cable lengths. Review the assumptions and installation notes as you adapt the circuit.
Main-current path only: B− goes to cell-pack negative and P− to the shared charger/load return. Cell taps, B+ supply, temperature sensors and activation wiring must follow the exact hardware revision's manual. The reference load determines example cable current; 300 A is the BMS limit. Cell protection trips are not simulated. Manufacturer installation manual
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Installation notes
Before you install.
Open a question for model-specific guidance and sources.
Verified against the manufacturer's documentation (rev. V19.0.1 (2025-03-14)), checked 2026-10-18. Manufacturer documentation →
Which JK BMS is this?
The JK-B2A8S30P, written JK-B2A8S-30P in Jikong's V19.0.1 manual, supports 300 A charging and discharging with up to 2 A active balancing. It suits 12/24 V LiFePO4 banks. This revision supports 3-8 LiFePO4 or Li-ion cells, and 7-8 LTO cells; check the installed revision rather than applying these ranges to older boards.
Bluetooth is standard. CAN, RS485, heating and parallel-pack support are optional configurations, not included features of this base entry.
Where do B− and P− connect?
B− connects to cell-pack negative; P− is the shared charger/load negative. Pack positive connects directly to the positive distribution. The BMS switches the negative path with MOSFETs. Its two power terminals do not represent the cell-sense harness, B+ supply, temperature sensors or communications.
The example shows only this main-current path. Use the manual's revision-specific harness instructions for pack assembly; the planner does not simulate cell protection trips.
Which settings and limits matter?
The manual lists 600 A instantaneous current without a duration. This is not a usable cranking rating or a fuse recommendation. Independent battery-circuit overcurrent protection is still required.
The factory low-temperature charging cutoff is −20°C, configurable in the app. Set it to the cell manufacturer's permitted charging range before use; the factory value does not establish safe cold charging.
Technical reference
Specifications and terminal map.
Check the model, ratings and connection points against your own unit before choosing installation hardware.
Catalog specification
300 A common-port BMS for 12/24 V banks with 2 A active balancing and Bluetooth. V19.0.1 supports 3–8S LiFePO4/Li-ion and 7–8S LTO. B− connects to pack negative; P− to chargers and loads. Cell taps, B+ supply and sensors are not drawn. Configure the −20°C factory charge cutoff for the cells; CAN, RS485 and heating are optional.
- Compatible systems
- 12 V / 24 V
Terminal map
B− is cell-pack negative; P− is the shared charger/load negative. Pack positive bypasses the switched path. These two terminals omit the required cell-sense, B+ supply and temperature-sensor harness; follow the complete manual before assembly.
B−
negative · input
P−
negative · output
Sources and sizing method
Equipment specifications. Model details, ratings and terminal roles come from the catalog. Check your unit’s label and current manufacturer documentation for its exact revision.
Example sizing. Cable labels apply to the connected example, not a fixed cable size for this component. Set your actual equipment, current, lengths and installation conditions in Crimp before choosing hardware.
Read how the sizing worksNext step
Plan your installation with B2A8S30P 300A.
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