12 – RS485 Modbus adapter
RS485
Transient voltage suppressors
Screwed terminals on the RS485 side
TX – RX Led indication for easy debugging and troubleshooting
Slew-Rate Limited for Error-Free Data Transmission (minimizing EMI and
reducing reflections caused by improperly terminated cables)
Drivers are short-circuit current limited
The receiver input has a fail-safe feature in case of broken connection
Compatible Devices: Any Modbus device capable of Modbus communication as a
master.
Speed reply time: better than 5 ms @ 57600 bauds
Max data packet: Any complete table provided in the Modbus data table
4.5 Commissioning process
To install the RS485 Modbus adapter, follow the hereafter commissioning process.
Disconnect power supply from the controller
Wait the required time to ensure all capacitors are discharged
Connect the signal ground (if present) to GND
Connect the twisted pair to the A and B connections
Insert the RS485 Modbus adapter in the controller
Fix it with the appropriate screw
Ensure that all connections are tight.
If the RS485 Modbus adapter is one of the two ending station on the
communication line put the load termination switch in the ‘ON ‘position. If not, put
it in the ‘OFF ‘position.
Make sure all other Modbus stations (master and slaves) are properly connected
Apply power on the controller
Enter the MODBUS menu under: