2. Main Features

1. Single slot design, easy installation in any position of FLEX I/O backplane

2. Support Modbus RTU and ASCII dual communication modes

3. Provide independent configuration port and communication application port

4. Isolated serial circuit design, strong anti-interference ability

5. Support multi-point bus connection, suitable for long-distance field communication

6. Complete LED status indication for convenient fault diagnosis

7. Compatible with all series of 1794 FLEX I/O modules

8. Support read and write access of Modbus coils, discrete inputs, holding registers and input registers

9. Built-in communication error detection and automatic reset function

10. Simple parameter configuration, stable operation and easy maintenance

3. Technical Specifications

3.1 Power Supply

3.2 Communication Interface

3.3 Environmental Parameters

3.4 Physical Parameters

4. LED Status Indication

1. PWR: Power indicator light, steady on means normal power supply

2. OK: Module running status light, steady on means module works normally

3. BP: Backplane communication indicator light, flashing means data transmission normally

4. COM: Modbus communication status light, flashing means normal receiving and sending data

5. ERR: Fault alarm light, on means communication failure or module abnormality

5. Installation Instruction

1. Cut off the power supply of FLEX I/O chassis before installation

2. Align the module with the chassis backplane slot and push it firmly in place

3. Fix the module locking buckle to ensure stable connection

4. Connect external 24VDC power supply and field communication cable

5. Power on the system and confirm all power indicators are on normally

6. Complete communication parameter configuration through upper computer software

6. Communication Function Description

1. Realize FLEX I/O analog quantity, switching quantity data upload to Modbus master station

2. Receive control commands issued by Modbus master station to control local I/O output

3. Support remote parameter modification and equipment status monitoring

4. Realize data interconnection between PLC system and third-party Modbus equipment

5. Support communication data address mapping and flexible address allocation

7. Application Scope

1. Automate production line Modbus network data acquisition

2. Power plant auxiliary equipment remote monitoring system

3. Petroleum and chemical field bus communication transformation

4. Water treatment and environmental protection equipment control system

5. Old industrial equipment Modbus communication upgrade and transformation

6. Multi-brand industrial control system data interconnection scheme

8. Safety Notes

1. Do not plug and unplug the module with power on to avoid device damage

2. All field wiring shall comply with industrial electrical safety specifications

3. Reasonably match communication baud rate and station address to avoid communication conflict

4. Regularly check wiring looseness and equipment heat dissipation condition

5. It is forbidden to use the module beyond the specified temperature and voltage range