Filter
Top Products
15 - 9
MELSEC-QnA
15 FUNCTIONS (FUNCTION VERSION B OR LATER)
15.5.4 Notes on using the standby master function
The following are the notes on using the standby master function.
1
There can be only one standby master station in a data link system.
2
The total number of stations is 64 including the standby master station. The number
of occupied stations for the standby master station is one or four.
3
Parameter registration to the standby master station is not necessary.
4
If an error is detected at the master station in the initial status (before parameter
communication starts), switching to the standby master station will not be executed.
5
When the master station becomes faulty, the polling issuing authority will switch
automatically to the standby master station, but the cyclic data transmission will not
switch. The switch must be enabled using the sequence program. Once the switch
has been enabled, the information up to the error detection at the master station will
be outputted to each remote station.
6
Parameters cannot be updated during the data link by the standby master station.
7
When the standby master station becomes faulty, the master station does not return
even after recovering its normal operation.
8
When the master station becomes faulty and the data link polling issue authority is
switched to the standby master station, the standby master station number
becomes an error number (Applicable bits of SB0080 and SW0080 to SW0083 are
turned ON).
When the standby master station is specified as an error invalid station, error
detection can be avoided.