Mitsubishi A(1S)J71QC24(N) Setup Guide

Introduction

The A(1S)J71QC24(N) computer link module allows data access software, such as Fernhill SCADA, to access a Mitsubishi QnA Series PLC data using a serial communications link. Fernhill SCADA is multi-protocol Data Access software for PLCs supporting OPC, ODBC, and ADO.NET.

The information in this guide applies to a range of Mitsubishi Melsec QnA Series computer link modules:

ModuleInterface
AJ71QC24One RS-232 plus one RS-422/485
AJ71QC24-R2Two RS-232
AJ71QC24-R4One RS-422 plus one RS-422/485
AJ71QC24NOne RS-232 plus one RS-422/485
AJ71QC24N-R2Two RS-232
AJ71QC24N-R4One RS-422 plus one RS-422/485
A1SJ71QC24One RS-232 plus one RS-422/485
A1SJ71QC24-R2Two RS-232

The remainder of this article uses the name AJ71QC24 to refer to any of the above modules.

There are two types of connection on the QnA-Series serial communication modules:

Connection TypeDescription
RS-232 DE-09RS-232 using a D-Subminiature 9 pin female connector
RS-422/485 Screw TerminalsRS-422/485 using a screw terminals

Connection Cables

To connect the RS-232 port on an AJ71QC24 to a D-Subminiature 9 pin serial port, typically found on a PC, a connection cable with this wiring is required:

AJ71QC24 RS-232
D-Subminiature connector DE-09 plug wiring side shown
PC
D-Subminiature connector DE-09 socket wiring side shown
RXD23TXD
TXD32RXD
DTR46DSR
GND55GND
DSR + DCD6 + 14DTR
RTS78CTS
CTS87RTS

Note: All other pins not shown in the above diagram have no connection.

Configuring Serial Communications

Setting up a serial communication link can be difficult because of the wide variety of communication options, for example Baud Rate, Frame Formats, Protocols and so on.

For Fernhill SCADA to successfully communicate with an AJ71QC24 module both the module and Fernhill SCADA need to use the same communication options. There are a two main ways to achieve this:

Manual Configuration

The AJ71QC24 module is configured by front panel switches.

Fernhill SCADA communications settings are configured by the Mode and CommFormat properties on the Mitsubishi Melsec serial channel and the StationNumber property on the Mitsubishi Melsec PLC Tag.

The relationship between AJ71QC24 front panel switches and Fernhill SCADA properties is:

Switch Fernhill SCADA Property
Station No StationNumber in the Mitsubishi Melsec PLC Tag
Mode CommFormat in the Mitsubishi Melsec serial channel
SW2-SW5, SW9-SW12 Mode in the Mitsubishi Melsec serial channel

These switches on the AJ71QC24 Computer Link module should be set to these positions for correct operation:

AJ71QC24 SwitchSetting
SW6On (Use sum check)
SW7On (Allow write during RUN)

Station No

The value of the StationNumber property of the Mitsubishi Melsec PLC Tag should match the value of the Station No switch on the communication module front panel.

Mode Switch

Fernhill SCADA supports communication modes 1, 2, 3, and 4. The CommFormat property of the Mitsubishi Melsec serial channel should be set to the matching value:

Mode SwitchCommFormat
1Format 1
2Format 2
3Format 3
4Format 4

Note: The AJ71QC24, AJ71QC24-R2, and AJ71QC24-R4 modules only support Format 1.

SW2

SW2 defines the number of data bits in each character transmitted on the communication channel. The Mode property of the Mitsubishi Melsec serial channel should contain a matching Data clause:

SW2Mode String Clause
OffData=7
OnData=8

SW3 and SW4

SW3 and SW4 define the parity bit added to each character transmitted on the communication channel. The Mode property of the Mitsubishi Melsec serial channel should contain a matching Parity clause:

SW3SW4Mode String Clause
OffN/AParity=N
OnOffParity=O
OnOnParity=E

SW5

SW5 defines the number of stop bits in each character transmitted on the communication channel. The Mode property of the Mitsubishi Melsec serial channel should contain a matching Stop clause:

SW5Mode String Clause
OffStop=1
OnStop=2

SW9 to SW11

SW9 to SW11 define the baud rate of the communication channel. The Mode property of the Mitsubishi Melsec serial channel should contain a matching Baud clause:

SW9 SW10 SW11 SW12 Mode String Clause
Off Off Off Off Baud=300
On Off Off Off Baud=600
Off On Off Off Baud=1200
On On Off Off Baud=2400
Off Off On Off Baud=4800
On Off On Off Baud=9600
Off On On Off Baud=19200
On On On Off Baud=38400
Off Off Off On Baud=14400
On Off Off On Baud=28800
Off On Off On Baud=57600
On On Off On Baud=115200

Example Configuration

This table shows an example switch settings for an AJ71QC24 module:

x10 x1
Station No 0 4
Ch1 Ch2
Mode 1 2
SW1 Off Off
SW2 On Off
SW3 On On
SW4 On Off
SW5 On Off
SW6 On On
SW7 On On
SW8 Off Off
SW9 Off On
SW10 On Off
SW11 On On
SW12 Off Off

The matching configuration in Fernhill SCADA would be:

ParameterCh 1Ch 2
Channel ModeBaud=19200 Data=8 Parity=E Stop=2Baud=9600 Data=7 Parity=O Stop=1
Channel CommFormatFormat 1Format 2
Device StationNumber44

For more information refer to the AJ71QC24 User's Manual.

Further Information

Mitsubishi Melsec Serial Autodetect Wizard

For how to automatically configure Fernhill SCADA to communicate with a Mitsubishi serial communication module.

Mitsubishi Melsec serial channel

For information about Mitsubishi Melsec serial channel configuration.

Mitsubishi Melsec PLC Tag

For information about Mitsubishi Melsec device configuration.

Serial Communications

For background information on serial communications.

Mitsubishi Melsec Driver

For information about the Mitsubishi Melsec Driver.

Glossary

For definitions of the terms used in Fernhill SCADA.