4.5
Command for record selection
4.5.1
Record selection
4.5.1.1
Function
Command records can be saved in a record table in the device. The command records contain para-
meters for processing commands and can be addressed by a record number. To start a command
record, e. g. via the device profile, the controlling PLC only needs to send the record number and the
start signal in the output data. The record table can be activated either as a foreground process or a
background process. However, motion commands can only be run as a foreground process
è
Tab. 262 Command record type parameter (ID Px.1810).
Start record table ...
Description
... as foreground pro-
cess
All command record types can be executed, including motion commands.
The event table can monitor events at the same time.
... as background pro-
cess
Motion commands are illegal and generate a category 1 stop.
The event table can monitor events at the same time.
Tab. 258 Mode of record table
Besides the parameters for pure command processing, record selection offers the following options
for influencing sequence control:
Options for sequence
control
Description
Record switching
A start condition can be established for every record. The start condition
specifies what the reaction should be to a start signal for the record if the
current command has not been ended yet (abort, wait, ignore, Px.1838).
Record sequencing
Command sequences that can be started with a single start signal can be
defined by sequencing records of the record table
è
Event table
Step enabling conditions that should be monitored in parallel can be
defined with the event table (
è
Tab. 259 Options for sequence control
Mode of record table
–
possible as background or foreground process
–
maximum 3 record sequences per command record
–
depending on the product variant and firmware: up to 128 command records and up to 128 record
links in total
The command records of the record table can be started as follows:
–
the device profile of the higher-order controller
–
the engineering interface, e. g. via the plug-in
Motion control
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Festo — CMMT-ST-SW — 2019-02
Содержание CMMT-ST-SW
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