Siemens 6MD662, Руководство пользователя

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Redundant PROFIBUS DP interface
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SIPROTEC PROFIBUS DP - Bus mapping 6MD662/3/4
C53000-L1840-B011-03
Every redundancy switchover always includes an internal communication via Red-
Com between the both modules of the redundant slave in order to ensure that both
modules never become PRIMARY at the same time.
Beside PRIMARY and BACKUP, the slave interfaces pass at least one intermediate
state during a redundancy switchover.
In these intermediate states
•
PB_Switchover or PB_Partner_Ack
during switchover from PRIMARY to BACKUP
•
BP_Switchover or BP_Partner_Ack
during switchover from BACKUP to PRIMARY
the modules wait for a response to a switchover request which was sent to the partner
module via RedCom or for a state change of the master device.
There is no evaluation of output data from the PROFIBUS DP master in the interme-
diate states, i.e. they behave like the BACKUP state.
The current redundancy states of the PROFIBUS DP modules on port B and port D
are shown in the module-specific information at the device display (ref. to chap. 1.5).
All possible redundancy states are described in Table 1-5.
Figure 1-12 shows a simplified state diagram of the redundancy switchover.
Figure 1-12 Redundancy switchover state diagram (simplified)
Master state: BACKUP
PRIMARY
Master state: PRIMARY
PB_Partner_Ack
Wait for Switchover.cnf
from partner module
Master state: PRIMARY
PB_Switchover
Wait for changeover of the
master state to BACKUP
Switchover.req
via RedCom
received
PRIMARY state
received
from master
BACKUP state
received
from master or
Switchover.cnf
via RedCom
received
RedCom:
Switchover.req
Partner modul
e
Slave m
o
d
u
le
BACKUP state
received
from master
Switchover.req
via RedCom
received
Switchover.cnf
via RedCom
received
PRIMARY state
received
from master
RedCom:
Switchover.req
Communic. interruption
Master state: PRIMARY
BP_Partner_Ack
Wait for Switchover.cnf
from partner module
Master state: BACKUP
BP_Switchover
Wait for changeover of the
master state to PRIMARY
BACKUP
Master state: BACKUP