2. BMS1802 Pinouts and Descriptions
On BMS1802 connector 1 carries the cell connections, connector 5 the external temperature sensors and connector 4 an external RUN LED. The isolated daisy chain has an INPUT port towards the master (ISO IN: RJ45 connector 2 and 4-pin connector 7) and an OUTPUT port to the next module (ISO OUT: RJ45 connector 3 and 4-pin connector 6); the two connectors of one port are the same lines, so use one of them, and the two ports cannot be swapped. Arrange the cables with the pinouts below; a number in the figures opens the table of that connector.
Danger
Check every connection and cable before you plug a connector into the BMS1802.
Table.2.1: Connector No#1 Descriptions
| Connector No. | Pin No. | Description (see Fig.2.1 and Fig.2.2) |
|---|---|---|
| 1 | 1, 2 | Bottom of the battery string, 1st cell's negative tab (C1-) |
| 1 | 3 | 3rd cell's positive tab (C3+) |
| 1 | 4 | 5th cell's positive tab (C5+) |
| 1 | 5 | 7th cell's positive tab (C7+) |
| 1 | 6 | 9th cell's positive tab (C9+) |
| 1 | 7 | 11th cell's positive tab (C11+) |
| 1 | 8 | 13th cell's positive tab (C13+) |
| 1 | 9 | 15th cell's positive tab (C15+) |
| 1 | 10 | 17th cell's positive tab (C17+) |
| 1 | 11 | 1st cell's positive tab (C1+) |
| 1 | 12 | 2nd cell's positive tab (C2+) |
| 1 | 13 | 4th cell's positive tab (C4+) |
| 1 | 14 | 6th cell's positive tab (C6+) |
| 1 | 15 | 8th cell's positive tab (C8+) |
| 1 | 16 | 10th cell's positive tab (C10+) |
| 1 | 17 | 12th cell's positive tab (C12+) |
| 1 | 18 | 14th cell's positive tab (C14+) |
| 1 | 19 | 16th cell's positive tab (C16+) |
| 1 | 20 | Top of the battery string, 18th cell's positive tab (C18+) |
Table.2.2: Connector No#2, #3 Descriptions
| Connector No. | Pin No. | Description (see Fig.2.1 and Fig.2.3) |
|---|---|---|
| 2 | - | Daisy-Chain INPUT Port (ISO IN), from the master or the previous module |
| 2 | 1, 2, 3, 4, 7, 8 | Not Connected |
| 2 | 5 | Isolated Daisy-Chain INPUT Port ISO- (isoSPI IMA) |
| 2 | 6 | Isolated Daisy-Chain INPUT Port ISO+ (isoSPI IPA) |
| 3 | - | Daisy-Chain OUTPUT Port (ISO OUT), to the next module |
| 3 | 1, 2, 3, 4, 7, 8 | Not Connected |
| 3 | 5 | Isolated Daisy-Chain OUTPUT Port ISO- (isoSPI IMB) |
| 3 | 6 | Isolated Daisy-Chain OUTPUT Port ISO+ (isoSPI IPB) |
Table.2.3: Connector No#4 Descriptions
| Connector No. | Pin No. | Description (see Fig.2.1 and Fig.2.3) |
|---|---|---|
| 4 | 1 | Positive pin of the RUN LED, lit while the module is awake (4.7 kΩ on the board, no external resistor needed) |
| 4 | 2 | STAT LED, not used |
| 4 | 3 | Negative pin of the RUN LED |
| 4 | 4 | STAT LED, not used |
Table.2.4: Connector No#5 Descriptions
| Connector No. | Pin No. | Description (see Fig.2.1 and Fig.2.3) |
|---|---|---|
| 5 | 1, 2, 3, 4, 5 | Ground (GND) of the temperature sensors |
| 5 | 6 | External Temperature Sensor No.5 (NTC5) |
| 5 | 7 | External Temperature Sensor No.4 (NTC4) |
| 5 | 8 | External Temperature Sensor No.3 (NTC3) |
| 5 | 9 | External Temperature Sensor No.2 (NTC2) |
| 5 | 10 | External Temperature Sensor No.1 (NTC1) |
Table.2.5: Connector No#6, #7 Descriptions
| Connector No. | Pin No. | Description (see Fig.2.1, Fig.2.3 and Fig.2.4) |
|---|---|---|
| 6 | - | Daisy-Chain OUTPUT Port (ISO OUT), the same lines as connector 3 |
| 6 | 1 | Isolated Daisy-Chain OUTPUT Port ISO+ (isoSPI IPB) |
| 6 | 2 | Isolated Daisy-Chain OUTPUT Port ISO- (isoSPI IMB) |
| 6 | 3 | Isolated Daisy-Chain OUTPUT Port ISO+ (isoSPI IPB) |
| 6 | 4 | Isolated Daisy-Chain OUTPUT Port ISO- (isoSPI IMB) |
| 7 | - | Daisy-Chain INPUT Port (ISO IN), the same lines as connector 2 |
| 7 | 1 | Isolated Daisy-Chain INPUT Port ISO+ (isoSPI IPA) |
| 7 | 2 | Isolated Daisy-Chain INPUT Port ISO- (isoSPI IMA) |
| 7 | 3 | Isolated Daisy-Chain INPUT Port ISO+ (isoSPI IPA) |
| 7 | 4 | Isolated Daisy-Chain INPUT Port ISO- (isoSPI IMA) |