Mitsubishi Electric QJ71LP21 Reference Manual page 220

8 TROUBLESHOOTING
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(2) Error history monitor details
Displays the causes of loop switches and the history of the transient transmission
errors.
1)
2)
3)
[Loop switching]
1) Requested by (SW00E0 to E7)
Displays the number of the station (not necessarily an adjacent station) that
requested the loop switch and loopback.
2) Factor (SW00D0 to DF)
Displays the reason why the loop switch and loop back are executed.
• Normal return
• Forward loop hardware error
• Reverse loop hardware error
3) Switched to (SW00D0 to DF)
Displays the data link status after the loop switch.
• Multiplex transmission: Forward loop/reverse loop normal
• Forward loop transmission
• Reverse loop transmission
• Loopback transmission
[Trasit transmission errors]
4) Err. code, Error type (SW00F0 to FF)
Displays the error code.
See Section 8.3
(3) Clear of error history
Select the check box of the items whose error history should be cleared from the
list of clear items. The error history can be cleared for each clear item.
4)
: Cable or optical module error
: Cable or optical module error
MELSEC-Q
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