Mitsubishi QJ71NT11B User Manual page 13

LED LED status
ERR. Red on
Flashing
Off
L ERR. Red on
Off
• An error occurred, for instance a station number setting error,
mode setting error (set to use prohibited), operation condition
setting error (parameters), or an installed CPU type error (settings
outside the range used, CPU type).
• A station with the same number already exists in the network.
• The host is specified as the control station even though a control
station already exists in the network.
• Invalid parameter settings.
• The parameters received from the sub-control station and the
parameters retained by the host (received from the control station)
are different.
• A moderate or fatal error occurred in the CPU module.
• An error was detected while testing the network module.
• The MODE switch or the STATION NO. switch status was
changed during operation.
Normal status
A communication error occurred (one of the following communication
errors has occurred):
CRC : Error generated by an cable failure, noise, etc.
OVER : This error occurs when the next data is received before
the last receive data is loaded into the module, and the
data is overwritten. It is caused by a hardware error in
the receive area of the network module.
AB.IF : This error occurs when more than the specified number
of bits are set to "1" among the receive data in the
frame, or when the receive data is shorter than the
specified data length.
TIME : This error occurs when a baton pass was not handed to
the host within the monitoring time.
DATA : This error is caused when abnormal code data is
received.
UNDER : This error occurs when the internal processing of the
send data was not executed at a fixed interval.
<Corrective action>
Check the cables and connectors (detached or loosened
connectors, wrong IN/OUT connections, broken or
damaged cables, improper cable routing, etc.)
For details, refer to "Network Diagnostics" (Q Corresponding
MELSECNET/H Network System Reference Manual
(PLC to PLC network)).
No communication error
Indication
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