Meanings Of The Led Displays - Mitsubishi QJ71DN91 User Manual

4 SETUP AND PROCEDURES BEFORE OPERATION

4.3.1 Meanings of the LED displays

QJ71DN91
RUN MS
NS
ERR.
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The following explains the names and meanings of the LEDs located on the top
surface of the QJ71DN91 when the mode is set to 0 to 8.
For the meanings of the LEDs when the mode is set to 9 to C, see Section 4.4,
"Hardware Test" or Section 4.6, "Communication Test".
Table 4.1 LED names and meanings of LED displays
LED name Color
RUN Green
ERR. Red
MS Green
NS Green
Red
Green/red
LED display status
On: In normal operation
Off: Watchdog timer error
On: Node number setting error
Flashing: The node number setting switch or mode setting switch was
changed during module operation.
On: Communication is enabled.
Flashing: parameter error
On: Communication in progress
Flashing: Waiting for communication (waiting for an I/O communication
request from the PLC CPU, or waiting for communication
startup of the opposite device)
On: The node number is duplicate with the node number of other node.
Bus off error (communication line error)
Flashing: <For master> A node that does not respond exists.
<For slave> Communication with the master node is
interrupted.
Off: Power to the network is not being supplied.
MELSEC-Q
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