ABB M101 - Handling of Redundancy Faults; Table 9 Primary and Backup IP Address Setting

REDUNDANCY HANDLING OF REDUNDANCY FAULTS
1TGC908004M0201 29
6.3. Handling of redundancy faults
Both MNS Digital Gateway supervise at all times the redundancy conditions, detecting
faults and problems according following table:
Event Action
PLC or DCS connection interrupted for more
than 1 second to Primary MNS Digital Gate-
way
Redundancy change over if backup MNS
Digital Gateway has an active PLC or DCS
c
o
n
n
ection
Power loss or internal error of Primary MNS
Digital Gateway
Redundancy change over,
Redundancy error indi-
cat
e
d
Power loss of backup MNS Digital Gateway
No cha
n
ge
ov
er, Re
d
un-
dancy error indicated
Problems in redundancy setup No change over possible,
Redundancy error indi-
cat
e
d
Switchgear Bus at Primary MNS Digital
Gateway disconnected
Redundancy change over
Table 9 Primary and Backup IP address setting
A change over from Primary to Backup MNS Digital Gateway will only be per-
formed if there is no redundancy error.
Nevertheless it is also possible that the DCS/PLC initiates a change over by
sending respective change over command. It needs to be ensured that the
switch over commands are configured in MNS Digital Gateway mapping for
the respective fieldbus.