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Communications
configuring
System- and communication configuring D7-SYS - SIMADYN D
3-263
Edition 12.2003
The ring should be initialized, so that a cascaded negation is generated.
As the DPI blocks internally initialize input IC with 0, the cycle can be
started by initializing a QC output with INIT = 1.
When interconnecting the cascade circuit, the prerequisites are as
follows:
•
All DPI blocks with the same device names (initialization input PHS)
should be connected with one another in a ring form via the IC/QC
connections.
•
The output QC of a DPI block in this ring, should be initialized with 1.
•
The DPI blocks of this ring should be configured in the same sampling
time as the associated central block. If this is not observed, this
doesn't result in erroneous operation, but however, has the
disadvantage that computation performance is unnecessarily used.
3.22.1.9
Parameter change report processing
The device can send parameter change reports. If a parameter change
report was sent, the normal task/response processing is interrupted until
the parameter change report is acknowledged. Variable-speed drives can
acknowledge parameter change reports from communication utility
parameter processing in two different ways:
•
The communications utility, parameter processing from variable-speed
drives (APR=1) automatically acknowledges parameter change
reports. The configuring engineer is not informed when a parameter
change report is received.
•
The user acknowledges the parameter change report (APR=0). In this
case, the user is informed about the parameter change report as the
parameter change report is applied to the appropriate outputs of the
central block. The user acknowledges the parameter change report by
setting input APR to 1. If this is then followed again by a manual
parameter change report acknowledgment, then connection APR
should be again set to 0.
3.22.1.10 Cyclic
tasks
The drive converter cyclically processes the task which has been issued
until the drive converter receives a new task. For responses, which
contain parameter values, the drive converter responds by repeating the
response telegram and that, always with the actual value. The PKW
blocks on the other hand provide each task with precisely one response.
If cyclic tasks are to be simulated, then input IC of the parameter block
should be cyclically negated .
3.22.1.11
Temporary error messages from the DPI blocks
If a task or response was not able to be correctly processed by a DPI
block, then it indicates this at its outputs. The following outputs are used:
Prerequisites
Description
Sequence
General
information