Communication adapter for MELSEC FX5
The FX5-485ADP is a serial communication adapter for the MELSEC FX5 series PLC, adding an RS-485/RS-422 port via a European terminal block. Photo-coupler isolation between the communication line and the CPU module protects the PLC from ground loops and transient voltages common in distributed field wiring. Baud rate selection spans 300 to 115200 bps, covering Modbus RTU and legacy device rates. Communication can be half-duplex or full-duplex, and the maximum cable length is 1200 m at 3937 feet.
Comparison with FX5-232ADP
When sourcing the FX5-485ADP against the FX5-232ADP, the critical difference is the physical layer: RS-485/422 via European terminal block versus RS-232C via 9-pin D-sub. This means the 485ADP cannot drop into a panel wired for the 232ADP without rewiring the connector and possibly changing the cable type. Maximum communication distance further distinguishes the pair: 1200 m for the 485ADP versus 15 m for the RS-232 variant. For plant-floor networks extending beyond a single cabinet, the 485ADP is the correct choice. Baud rate range and photo-coupler isolation are identical between the two adapters, so protocol compatibility and isolation performance are consistent if the physical layer is matched.
Sourcing and lifecycle posture
Serial communication adapters for the MELSEC FX5 series are specified as a BOM line item for distributed I/O networks. When ordering, specify the FX5-485ADP against an RFQ to confirm lead time (estimated 1–10 working days) and binding pricing.