Siemens sinamics dcp - Page 411

Operation
7.22 Connecting several SINAMICS DCPs in parallel
SINAMICS DCP
Operating Instructions, 09/2019, A5E34382853K
409
● Diagnostics
The actual operating state of all devices, which are connected via the parallel interface, is
indicated at each device in parameter r51816.
The assignment of the indices of r51816 is realized via the station addresses of the
devices. r51816[station address - 1].
The values in r51816 correspond to parameter r52800 of the individual stations.
Depending on the state of the communication to the individual stations, the following
values can be indicated in r51816:
– r51816 [station address - 1] = 999:
Since running-up, no data has been received from this station address.
– r51816 [station address - 1] = 998:
Since running-up, data has been received from this station address; however,
communication is currently interrupted.
Connection to fieldbuses
From the perspective of the fieldbus, each individual DCP connected in parallel is a fieldbus
participant/node. From the fieldbus perspective, it is not possible to treat several
SINAMICS DCP devices connected in parallel just like an individual DCP.
Current setpoint
Depending on the parallel interface configuration, the slaves take the current setpoint from
the master or from other sources, e.g. a fieldbus or analog inputs:
● Current setpoint from the master (p51800 of the slaves = 11)
Only the master has to be supplied with a current setpoint.
For n slaves, the setpoint of the master then refers to the sum of the reference currents
(r50072) of all devices connected in parallel; i.e. the (n+1) x the current of an individual
device is set.
● Current setpoint from a fieldbus or analog inputs (p51800 of the slaves = 21, 22)
The master and each individual slave must be supplied with its own current setpoint.
The current setpoint then refers to the reference current (r50072) of the individual
devices.
Actual values
The master and each slave supply their own actual values via the fieldbus.
The actual values of the individual devices must be added to determine the total current and
the total power of the devices connected in parallel.