Modbus Configuration
Address
This setting sets instrument address for connection to the RS-485 Modbus interface. The Internal (local) sensor has a default node address of 1. An external (X10 Remote) sensor will have a default address of 2.
To set the address:
| • | On the Configure tab, navigate to the Modbus Address, select 1-247 and save the setting. |
WARNING!
Ensure all instruments on the RS-485 bus have been configured with unique node addresses. If two instruments have been configured with same address, bus contention will occur, preventing communications with these instruments via the RS-485 interface.
Failure to follow this warning can result in serious personal injury or death.
Baud Rate
Sets instrument baud rate for connection to RS-485 Modbus interface. (Default: 9600 baud) To set baud rate:
| • | On the Configure tab under Modbus settings, locate Baud Rate, and select 9600/19200, and select OK to confirm |
Stop Bits
Sets instrument stop bits for connection to RS-485 Modbus interface. (Default: 1 stop bits) To set number of stop bits:
| • | On the Configure tab under Modbus settings, locate Stop Bits, select 1 or 2, and select OK to confirm |
Parity
Sets instrument parity for connection to RS-485 Modbus interface. (Default: None) To set parity:
| • | On the Configure tab under Modbus settings, locate Parity, select None/Odd/Even, and select OK to confirm |
Enable 120Ω Termination
For optimal communication reliability, in RS-485 Modbus networks, the last instrument physically connected to the RS-485 bus must include a 120Ω termination resistor. This is to reduce the potential for electrical signal reflection on long buses due to impedance mismatches.
The X30 X50 instruments include a termination resistor on all of the instruments. Please reference the operating manual (PN: 10253483) for an image of the location of the TERMINATE switch on each model's circuit board.
WARNING!
The termination resistor should only be enabled on the last instrument physically connected to RS-485 bus. An external resistor should not be connected where this is enabled on the instrument.
Failure to follow this warning can result in serious personal injury or death.