Yokogawa Data Acquisition with PID Control CX2000 - Manual (Page 123)

5-13
IM 04L31A01-17E
5
Ladder Communication Protocol
5.5 Communication Program for MELSEC
Below is a program example for communications between the CX and the MELSEC
Q02HCPU sequencer made by Mitsubishi Electric Corporation.
Preparations before Communications
Devices Used
This sample program assumes that the QJ71C24 computer module (communication
module) is installed into slot 2 of the Q02HCPU.
Connection
Connect the RS422 terminal of the QJ71C24 computer link unit to the CX according
to the figure below.
MELSEC
Computer Link Module
QJ71C24
Terminator
120 Ω, 1/2 W or more
CX
SDB (+)
SDA (–)
RDB (+)
RDA (–)
SG
SDA (+)
SDB (–)
RDA (+)
RDB (–)
SG
SHIELD
Use the PC software program for MELSEC and set the I/O assignments and their switch
settings as follows:
I/O Assignments
Slot Type Model Number of Points
CPU CPU
2(*-2) Intelligent QJ71C24 32
I/O Assignment Switch Setting
Slot Type Model Switch 1 Switch 2 Switch 3 Switch 4 Switch 5
CPU CPU
2(*-2) Intelligent QJ71C24 0000 0000 0582 0006 0000