Communication Stops During Operation - Mitsubishi Electric 800 Series Instruction Manual

9.3

Communication stops during operation

• Check that the option unit (FR-A8NC) and CC-Link dedicated cables are fitted properly. (Check for contact fault, break in the
cable, etc.)
• Check that the programmable controller program is executed properly.
• Check that data communication has not stopped due to an instantaneous power failure, etc.
LED status
Inverters (FR-A8NC)
Master
unit
Station 1
RUN●
L.RUN○
SD*
RD●
L.ERR○
RUN●
TIME○ L.RUN●
LINE○ SD●
or RD●
TIME● L.ERR○
LINE○
RUN●
L.RUN●
SD●
RD●
L.ERR○
100
HOW TO CHECK FOR ERROR USING THE LEDS
Station 2 Station 3
RUN● RUN●
Since the L.RUN LEDs of the FR-A8NC on
L.RUN● L.RUN○
station 1 and the FR-A8NC on station 3 are off,
SD● SD*
the station numbers of the inverters set as
RD● RD●
stations 1 and 3 are the same.
L.ERR○ L.ERR○
RUN● RUN●
Since the L.RUN and SD LEDs of the FR-
L.RUN○ L.RUN●
A8NC on station 2 are off, the transmission
SD○ SD●
speed setting of the FR-A8NC on station 2 is
RD● RD●
wrong within the setting range (0 to 4).
L.ERR○ L.ERR○
RUN● RUN●
Since the L.ERR LED of the FR-A8NC on
L.RUN● L.RUN●
station 3 flickers, the setting switch of the FR-
SD● SD●
A8NC on station 3 was moved during normal
RD● RD●
operation.
L.ERR○ L.ERR
Cause
After correcting the repeated
station numbers of the inverters
using Pr.542 Communication
station number (CC-Link),
switch power on again.
After correcting the transmission
speed setting using Pr.543 Baud
rate selection (CC-Link), switch
power on again.
After returning the setting switch
of the FR-A8NC to the original
position using Pr.542
Communication station
number (CC-Link) or Pr.543
Baud rate selection (CC-Link)
power on the inverter again.
Corrective action