4.5. Profibus DP-V2 functions
— Option —
In addition to the cyclic Profibus DP-V0 process data exchange and in addition to
the acyclic Profibus DP-V1 data exchange, the Profibus DP-V2 functions define
further, more comprehensive functions:
●
Isochronous mode
●
Cross traffic between slaves
●
Upload and download
●
Redundancy
●
Time synchronisation with time stamp
The actuator controls AUMATIC AC 01.2 supports the following functions:
●
Redundancy
●
Time synchronisation with time stamp
This means the two functions are only available combined. If only the time
synchronisation with time stamp is exclusively required, the redundant channel can
remain unconnected (connection with Profibus DP master not imperatively required.)
Profibus DP-V2 functions can be activated via the following parameters: Device
configuration > Application functions > Activation > Profibus DP-V2 M0587
4.5.1. Profibus DP-V2 redundancy
The behaviour and the states of a redundant slave are defined in the "Specification
Slave Redundancy 2.212" (also refer to <Redundant behaviour according to Profibus
DP-V2 redundancy (PNO guideline 2.212)>). A distinction is made between a primary
and a backup channel, with different effects on the properties of Profibus DP
communication:
●
Cyclic Profibus DP-V0 communication
- Operation commands of the primary channel are processed and executed
by the actuator; operation commands by the backup channel are ignored,
the communication for the backup channel is only used for monitoring.
- Feedback signals of the actuator can be sent via both channels.
- Diagnostic feedback signals of the primary channel contain diagnostic
status data of both the primary and the backup channel.
●
Acyclic Profibus DP-V1 services of the controls (DPM1 = master class 1) are
only supported by the primary channel.
●
Acyclic Profibus DP-V1 services of the engineering stations (DPM2 = master
class 2) are only supported by the primary channel.
Furthermore, a distinction is made between two configuration types within the Profibus
DP-V2 redundancy:
Flying redundancy (FR)
●
The slave address of the primary channel is different from the address of the
backup channel (slave address backup = slave address primary + 64, for this
reason the slave address of the primary must be < 62).
●
Only the slave address of the primary channel has to be set.
●
The master never communicates via the backup channel with the slave.
System redundancy (SR)
●
The slave address of the primary channel corresponds to the slave address of
the backup channel.
●
The master can configure both channels and can establish a cyclic DP-V0
connection via both channels.
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Actuator controls
Description of the data interface AC 01.2/ACExC 01.2 Profibus DP