5. SETTINGS AND PROCEDURES BEFORE OPERATION
5
−
5
MELSEC-A
A
J71DN91
RUN
L.RUN
NS
MS
A
1SJ71DN91
RUN
L.RUN
MS
NS
5.4 LED Displays and Indicator Descriptions
This section describes the names of the LEDs at the top of the AJ71DN91 and A1SJ71DN91
front panel and provides indicator descriptions.
LED
Name
Color
Description
LED Display Status
Lit
Normal operation
Unit error detected
No power supply
Not lit
Parameters being loaded
Unit error detected
RUN
Red
Normal opera-
tion display
Flashing
Parameters being loaded
Lit
Communicating
Not lit
Communication stopped
Flashing (periodic)
Preparing for communication
L.RUN
Red
Communication
status display
Flashing (random)
Communication parameter error
Lit
DeviceNet interface unit operating
normally
Green
Module status
display
Flashing
Parameter error
MS
Red
Module status
display
Not used
Lit
Communication enabled with on-line
slave stations
Green
Network status
display
Flashing
Communication not enabled with on-
line slave stations
Duplicate MAC ID error
Lit
Bus-off error occurred
NS
Red
Network status
display
Flashing
There is a connection that has timed
out.