1 port RS232 (Port3) + 1 port RS485 (Port4) communication module.
| Specification | FBs-CM25 |
| RS232 Port | 1 port (Port3) |
| RS485 Port | 1 port (Port4) |
| Indicators | Each Port has its own TX, RX LED indicators |
| Wiring mechanis | DB9F, 3 pins spring terminal |