2.1 Installation procedure
The mounting area of the BMS Logic 18 must be protected from mechanical particles (dust, dirt, large objects) and water. The BMS Logic 18 is recommended to be placed close to the cells it controls, but away from high current circuits to reduce interference to measuring circuits and increase overall reliability of installation.
The installation site must provide convenient access for subsequent connection to the device’s headers.
The BMS Logic 18 has a heat sink to dissipate the heat generated during the balancing of the cells. When used in enclosed enclosures, heat must be removed from the sink, otherwise it may damage the device.
Overall and mounting dimensions of the BMS Logic 18 are shown below.
| Parameter | Value |
Overall dimensions (length × width × height), mm | 214 × 140 × 16 |
| Mounting dimensions (length × width), mm | 198 × 132 |
| Mounting holes | M4 |
| Headers X1-X5 type | Molex series Micro-Fit |
2.2 Headers
The BMS Logic 18 is designed to measure temperature and voltage of 18 battery cells.
2.2.1 X1 – header for cells
| Pin | Name | Description |
| 1 | V- | Minus of the cell stack |
| 2 | C2 | Cell #2 |
| 3 | C4 | Cell #4 |
| 4 | C6 | Cell #6 |
| 5 | C8 | Cell #8 |
| 6 | C10 | Cell #10 |
| 7 | C12 | Cell #12 |
| 8 | C14 | Cell #14 |
| 9 | C16 | Cell #16 |
| 10 | C18 | Cell #18 (maximum potential of the cell stack) |
| 11 | - | - |
| 12 | C1 | Cell #1 (minimum potential with respect to V-) |
| 13 | C3 | Cell #3 |
| 14 | C5 | Cell #5 |
| 15 | C7 | Cell #7 |
| 16 | C9 | Cell #9 |
| 17 | C11 | Cell #11 |
| 18 | C13 | Cell #13 |
| 19 | C15 | Cell #15 |
| 20 | C17 | Cell #17 |
2.2.2 X2 – header 1 for temperature sensors
| Pin | Name | Description |
| 1 | TEMPG9 | Ground of the thermistor #9 |
| 2 | TEMPG8 | Ground of the thermistor #8 |
| 3 | TEMPG7 | Ground of the thermistor #7 |
| 4 | TEMPG6 | Ground of the thermistor #6 |
| 5 | TEMPG5 | Ground of the thermistor #5 |
| 6 | TEMPG4 | Ground of the thermistor #4 |
| 7 | TEMPG3 | Ground of the thermistor #3 |
| 8 | TEMPG2 | Ground of the thermistor #2 |
| 9 | TEMPG1 | Ground of the thermistor #1 |
| 10 | TEMP9 | Signal from the thermistor #9 |
| 11 | TEMP8 | Signal from the thermistor #8 |
| 12 | TEMP7 | Signal from the thermistor #7 |
| 13 | TEMP6 | Signal from the thermistor #6 |
| 14 | TEMP5 | Signal from the thermistor #5 |
| 15 | TEMP4 | Signal from the thermistor #4 |
| 16 | TEMP3 | Signal from the thermistor #3 |
| 17 | TEMP2 | Signal from the thermistor #2 |
| 18 | TEMP1 | Signal from the thermistor #1 |
2.2.3 X3 – header 2 for temperature sensors
| Pin | Name | Description |
| 1 | TEMPG18 | Ground of the thermistor #18 |
| 2 | TEMPG17 | Ground of the thermistor #17 |
| 3 | TEMPG16 | Ground of the thermistor #16 |
| 4 | TEMPG15 | Ground of the thermistor #15 |
| 5 | TEMPG14 | Ground of the thermistor #14 |
| 6 | TEMPG13 | Ground of the thermistor #13 |
| 7 | TEMPG12 | Ground of the thermistor #12 |
| 8 | TEMPG11 | Ground of the thermistor #11 |
| 9 | TEMPG10 | Ground of the thermistor #10 |
| 10 | TEMP18 | Signal from the thermistor #18 |
| 11 | TEMP17 | Signal from the thermistor #17 |
| 12 | TEMP16 | Signal from the thermistor #16 |
| 13 | TEMP15 | Signal from the thermistor #15 |
| 14 | TEMP14 | Signal from the thermistor #14 |
| 15 | TEMP13 | Signal from the thermistor #13 |
| 16 | TEMP12 | Signal from the thermistor #12 |
| 17 | TEMP11 | Signal from the thermistor #11 |
| 18 | TEMP10 | Signal from the thermistor #10 |
2.3.4 X4, X5 – headers for communication with BMS Main
| Pin | Name | Description |
| 1 | RS485_A | RS-485 line A for communication with the BMS Main |
| 2 | RS485_B | RS-485 line B for communication with the BMS Main |
| 3 | +5V | Supply voltage 5V |
| 4 | GND | Ground |
2.4 Switches and Indicators
2.4.1 SWD1 – address switch
| Switch number | Description |
| 1 | The first (the lowest) bit of the address. Position ON - bit is 1 |
| 2 | The second bit is the address. Position ON - bit is 1 |
| 3 | The third bit of the address. Position ON - bit is 1 |
| 4 | The fourth bit of the address. Position ON - bit is 1 |
| 5 | The fifth (the highest) bit of the address. Position ON - bit is 1 |
2.4.2 SWD2 – RS-485 termination resistor switch
To connect the termination resistor between the RS485_A and RS485_B lines, switch SWD2 to the ON position.
2.4.3 DS1 – mode indicator
| State | Description |
| Blinking | Connection between the BMS Main and the device is established |
| Short flashing (~50 milliseconds in a second) | The device is measuring voltage and temperature. No communication between the BMS Main and the device |
| Long flashing (1 second in a 2 second period) | The device is in the bootloader mode |