IDEC MicroSmart - Manual (Page 282)

17: U SER C OMMUNICATION I NSTRUCTIONS
17-4 « FC4A M ICRO S MART U SER ’ S M ANUAL »
Connecting RS485 Equipment through RS485 Port 2
Upgraded slim type CPU modules can use the RS485 user communication function. Using the RS485 user communica-
tion, a maximum of 31 RS485 devices can be connected to the
MicroSmart CPU module.
When using port 2 for RS485 communication on the slim type CPU module, mount the RS485 communication module
(FC4A-HPC3) next to the CPU module.
When using port 2 for RS485 communication on the slim type CPU module with the optional HMI module, install the
RS485 communication adapter (FC4A-PC3) to the port 2 connector on the HMI base module (FC4A-HPH1).
Connect RS485 device to the RS485 terminals A, B, and SG of port 2 on the MicroSmart CPU module using a shielded
twisted pair cable as shown below. The total length of the cable for the RS485 user communication can be extended up to
200 meters (656 feet).
RS485 User Communication System Setup
31 devices maximum
RS485 Device
RS485 Device RS485 Device
Shielded twisted pair cable
200 meters (656 feet) maximum
Core wire 0.3 mm
2
Por t 2
RS485 Communication Adapter
FC4A-PC3
HMI Base Module
FC4A-HPH1
Por t 2
RS485 Communication Module
FC4A-HPC3