Mitsubishi Electric Melsec QJ71LP21 Reference Manual page 109

4 SETUP AND PROCEDURES BEFORE STARTING THE OPERATION
Name LED status
L ERR. ON (red)
OFF
ON (green)
EXT. PW
OFF
1: The ERR. LED flashes on the following modules whose serial No. (first five digits) is "02112" or later.
• QJ71LP21
• QJ71LP21-25
• QJ71BR11
STATION NO.
10
1
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A communication error occurred (one of the following communication errors has occurred):
CRC : An error was generated by a fault such as a cable error and noise.
OVER : This error occurs when the next data is received before the last receive data is loaded
into the module, and the previous data is lost. It is caused by hardware failure in the
receive area of the network module.
AB.IF : This error occurs when the number of receive bit data indicating "1" in the frame is
more than or equal to the specified number of data, 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 occurs 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.
LOOP : This error occurs when the forward loop line or reverse loop line is faulty and the power
to the adjacent station, which sends data to the host station, is turned off or the
hardware of the sending station part in the loop is faulty.
<Corrective action>
Check the cables and connectors (e.g. disconnected or loosened connector, wrong
IN/OUT connection, disconnected cable, damaged connector/cable, improper cable
routing).
For details, refer to the network diagnostics (Section 8.1).
No communication error
External power being supplied (Power supply status of host (SB0042) is on.)
External power not supplied (Power supply status of host (SB0042) is off.)
(2) Station number setting switch
Used to set the station number of the network module. (Factory default: 1)
Setting
0
10 10s unit
1 to 64
1 1s unit
65 to 99
POINT
(1) Station numbers cannot be duplicated in the same network.
(2) Any station can be set as the control station as long as the station number is
within the setting range.
(3) The station number can be set randomly. Note that stations with no number
assignment must be set as reserved stations.
(4) When setting, use a station number within the range set to "Total stations"
parameter of network parameter.
Description
Description
Setting error
(The ERR. LED turns on.)
Station number 1 to 64
Setting error
(The ERR. LED turns on.)
MELSEC-Q
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