FX3U-485-ADP-MB RS-485 Communication Adapter for FX3U | Mitsubishi Electric

The Original New Mitsubishi Electric FX3U-485-ADP-MB is a communication special adapter designed for the MELSEC-F FX3U series programmable logic controller (PLC) system. It connects directly to the left side of the FX3U main unit and provides one isolated RS-485 communication channel, enabling the PLC to function as either a Modbus RTU/ASCII master or slave station. The adapter supports multiple communication methods including Modbus, computer link, parallel link, N:N network, and Mitsubishi inverter communication, making it a versatile solution for integrating third-party devices such as variable frequency drives, HMI panels, temperature controllers, and remote I/O stations. Photocoupler isolation ensures reliable signal transmission in electrically noisy industrial environments.

Core Engineering Highlights:
1 x RS-485 isolated communication channel | Half-duplex bidirectional communication | Transmission speed: 300 to 115200 bps | Maximum transmission distance: 500 m | Modbus RTU/ASCII (master/slave) | Photocoupler isolation | Built-in terminal resistor selector switch (330 Ω / OPEN / 110 Ω) | 17.6 mm width | 0.08 kg | 0°C to +55°C operating temperature

Key Features:

• Original New Mitsubishi Electric FX3U-485-ADP-MB adapter

• 1 x RS-485 isolated communication channel for the FX3U PLC system

• Supports Modbus RTU/ASCII communication in both master and slave modes

• Up to 32 slave devices can be controlled by one master station in Modbus RTU mode

• Photocoupler isolation ensures reliable, interference-free data transmission

• Built-in terminal resistor selector switch (330 Ω / OPEN / 110 Ω) simplifies network termination

• LED status indicators: POWER (green), RD (receive data, green), SD (send data, green)

• European-type removable terminal block for field wiring

• Occupies 0 I/O points (does not consume PLC I/O allocation)

• Connects to the left side of FX3U main unit

• Supports dedicated communication instructions (RS/RS2) for non-protocol and inverter communication

• Maximum read data (Modbus): 125 words or 2000 coils

• Maximum write data (Modbus): 123 words or 1968 coils

• DIN rail mounting

Applications:

• Modbus RTU/ASCII networking with inverters, HMIs, sensors, and actuators

• Multi-drop RS-485 communication between FX3U PLCs and third-party devices

• Inverter parameter setting and monitoring via Mitsubishi inverter protocol

• Temperature control systems with PID closed-loop control

• Remote sensor and I/O station integration

• Legacy system upgrades requiring Modbus connectivity for FX2N/FX3U configurations

Technical Specifications:

System Compatibility:

• Compatible with Mitsubishi Electric MELSEC-F series FX3U, FX3UC, FX3G, FX3GC, and FX3S PLCs. Drive model and firmware compatibility should be verified before installation.

• Connects to the left side of the PLC main unit

• For FX3S connection, FX3S-CNV-ADP is required

• For FX3G connection, FX3G-CNV-ADP is required

• For FX3U connection, a function expansion board is required when connecting to FX3UC-32MT-LT(-2)

• Maximum 2 special adapters can be connected to FX3U/FX3UC main units

• Modbus functionality requires main unit firmware version 2.40 or later

Related Products:

• FX3U-232ADP-MB – RS-232 communication adapter for FX3U (complementary)

• FX3U-485-BD – RS-485 function expansion board (non-isolated, 50 m)

• FX3G-485-BD – RS-485 function expansion board for FX3G

• FX3U-422-BD – RS-422 function expansion board

• FX3U-ENET-ADP – Ethernet adapter for FX3U

• FX3U-4AD-ADP – 4-channel analog input adapter

• FX3S-CNV-ADP – Conversion adapter for FX3S connection

• FX3G-CNV-ADP – Conversion adapter for FX3G connection

PLC ERA is an independent industrial automation distributor supplying genuine Original New products through established global supply channels. All products are factory sealed when applicable and undergo quality inspection prior to shipment. Mitsubishi Electric and MELSEC are trademarks of Mitsubishi Electric Corporation.