AUMA AUMATIC AC 01.2 Manual page 45

Actuator controls
AC 01.2/ACExC 01.2 Profibus DP
Table 33: Structure of the PrmCmd parameter command
Byte Bit
7 6 5
1 0 0 0
2 0 0 0
3 0 0 0
4 Sequence number
Figure 4: Configuration type for Profibus DP-V2
Setting the bus address (slave address)
Each channel has its own address. After setting the primary address, the backup
automatically accepts the address of the primary plus a configurable offset (either 0
or 64).
Startup behaviour
The channels automatically change between the startup_primary and startup_waiting
states until the master starts the communication with the actuator. In the
startup_primary state, the actuator waits with the primary slave address for the master
to start the communication. The cycle starts with 2 s, this time is doubled after each
cycle to max. 32 s.
Change over
The actuator does not decide autonomously on change-over. The master detects a
loss of communication of the primary channel and may initiate change-over using a
parameter telegram (parameter command PrmCmd). The former backup channel
becomes the new primary channel.
Parameter command
Apart from the change-over commands, different parameters for the configuration
of the Profibus DP-V2 redundancy are transmitted using the PrmCmd parameter
command.
For Profibus DP-V2, the parameter command is part of the parameter telegram which
is sent to the actuator on startup of the communication.
4 3 2
0 1 0
0 0 0
0 0 0
Reserved
Description of the data interface
1 0
0 0
1 0
0 0
Remark
Block length (= 0x08)
Structure type (= 0x02,
PrmCmd parameter
command for DP-V2
redundancy
Slot
Specifier
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