Factory Automation

MELSEC-F series Parallel Link

Features

  • 1. Data link between two FX PLC main units can be made easily just by programming to specify master/slave station.
  • 2. Bit devices (50 to 100 points) and word devices (10 points) are automatically linked between each station. Depending on the devices allocated in the host station, the ON/OFF states and data register values of the other station can be known.

Applicable communication device

RS-485 communication device

Model Applicable FX PLC
FX
3S 		FX
3G 		FX
3U 		FX
3GC 		FX
3UC
Function expansion board FX3G-485-BD *5
○
Max.
1 unit 		○
Max.
2 units
*1 		× × ×
FX3G-485-BD-RJ *5
○
Max.
1 unit 		○
Max.
2 units
*1 		× × ×
FX3U-485-BD

Order acceptance:
March, 2028
Production discontinuation:
September, 2028

× × ○
Max.
1 unit 		× *2
○
Max.
1 unit
Specific adapter FX3U-485ADP-MB *6
○
Max.
1 unit 		*3
○
Max.
2 units
*1 		*4
○
Max.
2 units 		○
Max.
2 units 		*4
○
Max.
2 units
  • *1 FX3G 14 pt, 24 pt models: 1 board. 40 pt, 60 pt models: 2 boards.
  • *2 Can be connected only to the FX3UC-32MT-LT(-2).
  • *3 When connecting to FX3G, FX3G-CNV-ADP is required.
  • *4 When connecting to FX3U, FX3UC-32MT-LT(-2), function expansion board is required.
  • *5 Function expansion board and FX3S-CNV-ADP cannot be used together.
  • *6 When connecting to FX3S, FX3S-CNV-ADP is required.

System configuration example

System configuration example

Specifications

Items Specifications
Transmission standard Conforms to RS-485 and RS-422 standards
Max. transmission distance When special adapter is used: 500 m
When function expansion board is used (including when special adapter and function expansion board are used together): 50 m
Communication method/Transmission speed Half-duplex bidirectional: 19200 bps, 115200 bps (FX3S, FX3G, FX3U, FX3GC, FX3UC)
Number of connectable units (configuration) 1 : 1
Link points FX3S [Master -> Slave]:
Bit device 50 points, word device 10 points (when high speed mode, word device 2 points)
[Slave -> Master]:
Bit device 50 points, word device 10 points (when high speed mode, word device 2 points)
FX3G, FX3U,
FX3GC, FX3UC 		[Master -> Slave]:
Bit device 100 points, word device 10 points (when high speed mode, word device 2 points)
[Slave -> Master]:
Bit device 100 points, word device 10 points (when high speed mode, word device 2 points)
Link time Regular mode: 70 ms *1 + master station operation cycle (ms) + slave station operation cycle (ms)
High speed mode: 20 ms *2 + master station operation cycle (ms) + slave station operation cycle (ms)
Combination with connectable PLC models
  • [FX3S and FX3S]
  • [FX3G, FX3GC and FX3G, FX3GC]
  • [FX3U, FX3UC and FX3U, FX3UC]
Connection device
with PLC 		FX3S FX3G-485-BD(-RJ), or FX3S-CNV-ADP + FX3U-485ADP-MB
FX3G FX3G-485-BD(-RJ), or FX3G-CNV-ADP + FX3U-485ADP-MB
FX3GC FX3U-485ADP-MB
FX3U, FX3UC *3 FX3U-485-BD, or function expansion board + FX3U-485ADP-MB
  • *1 FX3S, FX3G, FX3GC, FX3U, FX3UC : 15 ms
  • *2 FX3S, FX3G, FX3GC, FX3U, FX3UC : 5 ms
  • *3 Function expansion board cannot be connected to FX3UC-**MT/D and FX3UC-**MT/DSS. Specific adapter can be directly connected.