Mitsubishi QJ71MT91 User Manual

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MELSEC-Q
11 TROUBLESHOOTING
11.4.2 Program example for use of sequence program
This section explains how to turn off the COM. ERR. LED from a sequence program.
(1) Relationship between COM.ERR. LED and I/O signals
Upon occurrence of a communication error, the COM.ERR. LED (COM.ERR.
LED status (X1B): ON) on the front of the QJ71MT91 turns ON. (1) in the figure)
(a) Turn ON the COM.ERR. LED OFF request (Y1B) to turn OFF the
COM.ERR. LED. (2) in the figure)
(LED OFF)
(LED ON) (LED ON)
Error
occurrence
Error
occurrence
Error
occurrence
Error occurrence
COM.ERR. LED OFF request (Y1B)
COM.ERR. LED status (X1B)
1) 2) 3) 1)
ON ON
(b) While the COM.ERR. LED OFF request (Y1B) is ON, OFF request
processing is performed continuously. (3) in the figure)
(c) The error information in the error log area of the buffer memory is not cleared
(erased) by turning ON the COM.ERR. LED OFF request (Y1B).
(2) Program conditions
In this program, COM. ERR. LED OFF request (Y1B) is turned on to turn off the
COM. ERR. LED.
Device Name Device Application
X0 Module READY
Input
X1B COM. ERR. LED status
QJ71MT91 input/output
Output Y1B COM. ERR. LED OFF request
External input (command) X20 COM. ERR. LED OFF command
(3) Program example
COM.ERR. LED
OFF request
COM.ERR.
LED OFF
request
COM.ERR.
LED OFF
request
COM.ERR.
LED status
COM.ERR.
LED OFF
command
Module
READY
COM.ERR.
LED status
COM.ERR. LED
OFF completed

Mitsubishi QJ71MT91 Specifications

General

Brand	Mitsubishi
Model	QJ71MT91
Category	Controller
Language	English