User Manual

Control concept
Superposed plant controls
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switch-on sequence. Independent switch-on and switch-off sequences are not
implemented in this block.
Switched on block can be monitored for their states. There is no monitoring of
the OFF status.
Prior to switching on a block a test is made to see if the conditions for
executing a command are given. The switch-on process is not even available
for active switch on delay, minimum switch off times or a switch command with
a higher command (e.g., a maintenance switch). This Look Ahead mechanism is
described in greater detail in this chapter.
This block does not contain interlocks of individual functional units within
aggregates. These are implemented locally via the data flow between the
relevant blocks.
Plant Control Editor
The block parameters are set in the Plant Control Editor.
The upper part of the dialog box serves primarily to provide a quick online
overview of the present plant operating mode. You can also define exception
value which become active as a plant operating mode during a plant fault.
The upper part of the table configures the sequences. The switch-on sequence
of the objects, the monitoring mode and the switch on and off types for the
sequence controllers can be defined here.
The lower part of the table is used to define the plant operating modes. You
can define what command at what priority is command per plant operating
mode for each sequence element.
The following priorities for commanding are available:
● Priority 2: Life safety, automatic
● Priority 5: Plant safety, automatic
● Priority 14: Specific command object
● Priority 16: System control
You can enable a command priority with the value Not command for plant
operating modes where the local control is intended to assume control of the
aggregate.
[DefVal] applies when the [PrioArr] for the corresponding block is empty, that
is, not active recognition set, at that time.
Function workflows in CMD_CTL
A series of safety, monitoring and switch actions are conducted for each
change to the plant operating mode in block CMD_CTL.