Standby Master Function; Operation Overview - Mitsubishi A1SJ61BT11 User Manual

15 FUNCTIONS (FUNCTION VERSION B OR LATER)

15.5 Standby Master Function

15.5.1 Operation overview

This function allows data link to continue when an error occurs at the master station, by
switching to the standby master station.
However, switching from the standby master station to the master station will not occur
automatically when the master station returns.
The operation overview of the standby master function is shown in Figure 15.3.
CPU device Master station
CPU device Master station
1: Accepts refresh from the CPU by the switching instruction of the special link relay
(SB0001).
2: The host area is retained/cleared (by the DIP switch).
Figure 15.3 Operation overview of the standby master function
R1
Remote output
R2
L3
Local station
(Standby master
station)
Master station down
R1
Remote output
R2
L3
Local station
(Standby master
station)
15 - 6
MELSEC-A
Remote input
CPU
Remote input
CPU
1
2