Station Number Overlap Checking Function - Mitsubishi MELSEC-Q Series User Manual

4 FUNCTIONS

4.4.11 Station number overlap checking function

4 - 62
This function investigates the status of connected stations and checks for the
overlapping numbers of occupied stations and whether or not more than one station
whose station number setting is 0 exists in the system.
(1) Occupied station number overlap checking
Checks whether or not occupied station numbers duplicate.
(Example)
Local station (station number 1,
number of occupied stations: 4)
Remote device station
(station number 4, number of occupied stations: 2)
1) When there is an duplicate, the "ERR." LED flashes, and the duplicate status
is stored in SW0098 to SW009B (Station number overlap status).
2) Even if an overlap exists, the data link continues with the remaining normally
functioning stations.
3) By correcting the switch setting to normal and resetting the PLC CPU of the
master station, the "ERR." LED is turned off and the data in SW0098 to
SW009B can be cleared.
However, if the starting station number overlaps, it is excluded from the overlap
checking.
(Example)
Local station (station
number 1, number of
occupied stations: 4)
Remote device station
(station number 1, number
of occupied stations: 2)
Check the other station data link status (SW0080 to SW0083) for a data link
error. The station number setting of the station where a data link error has
occurred may be wrong.
(2) Station number 0 station overlap checking
Checks whether or not more than one station whose station number setting is 0
exists in the system.
1) When duplicating, the "ERR." LED lights up, an error code is stored in
SW006A (switch setting status), and SB006A (switch setting status) turns on.
2) By correcting the switch setting to normal and restarting the data link, the
"ERR." LED is turned off and the data in SW006A can be cleared.
Station Station
number 1 number 2
Station Station Station
number 1 number 2 number 3
Duplicate
Station Station
number 1 number 2
MELSEC-Q
Station Station
number 3 number 4
Duplicate
Station Station
number 4 number 5
Station Station Station
number 4 number 5 number 6
4 - 62