When to use: Use when laying out a BACnet MS/TP trunk over RS-485. Each segment is limited to 32 unit loads (without a repeater), 127 master addresses (Max_Master), and 1200 m (4000 ft) of cable with EOL termination at both ends. As device count and baud rate change, the token rotation time changes — keep it under ~1 s for responsive control. Higher baud (38400–115200) supports faster rotation but shorter practical cable runs.