BACnet MS/TP (Master-Slave/Token-Passing) uses RS-485 twisted pair for building automation networking between thermostats, VAV controllers, and BACnet devices at up to 76.8 kbps.
| Pin | Name | Function | Type |
|---|---|---|---|
| 1 | Data+ | RS-485 non-inverting positive | BUS |
| 2 | Data- | RS-485 inverting negative | BUS |
| 3 | GND | Ground reference | GND |