Troubleshooting When Communication Error "Ch1 Err.", "Ch2 Err." Generate - Mitsubishi QJ71C24/-R2 User Manual

10 TROUBLESHOOTING

10.3.10 Troubleshooting when communication error "CH1 ERR.", "CH2 ERR." generate

Symptom
• "ERR." LED turned on.
10 - 37
Cause
• There is an error in the
communication protocol
or transmission setting.
• There is an error in the
on-line mode switching
designation.
• On-demand execution
generated an error.
• The Q series C24
detected an error while
transmitting data.
• The Q series C24
detected an error while
receiving data.
Note
• When the "ERR." LED is turned on, the error code is stored to the following buffer memory.
Error cause
Switch setting error
Mode switching error
On-demand execution
error
Data transmission error
Data receive error
Modern function error
MC protocol
transmission error
Monitoring device error
See Section 10.2 for a detailed description of the error codes.
Corrective action
• Read the error code from the buffer memory
and check the error contents and change the
switch setting to the correct setting.
• Read the error code from the buffer memory
and check the error contents and correct the
designation contents.
• Read the error code from the buffer memory
and check the error contents and correct the
designation contents.
• Read the error code from the buffer memory
and take the corrective action corresponding to
the error contents.
• Read the error code from the buffer memory
and take the corrective action corresponding to
the error contents.
Error code storage buffer memory
Address
CH1 CH2
203 Switch setting error, mode switching error storage area
H
256 266 On-demand execution result storage area
H H
257 267 Data transmission result storage area
H H
258 268 Data receive result storage area
H H
221 Modern function error code storage area
H
025A 026A MC protocol transmission error code
H H
2205 2305 PLC CPU monitoring function execution result
H H
MELSEC-Q
MC
Name
10 - 37