User Manual

Control concept
Superposed plant controls
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The power data in the object table and the sequence entries in the profile table
in Figure
Example of aggregate table together give the power profile illustrated
in Figure
Example of profile entries with a drop in power (Profile 2) .
Profile 1
In the main application of the PWR_CTL function, a new energy producer is
added for each sequence entry in the profile table. For this purpose, an
aggregate only needs to be entered in the sequence table once.
In the event of a power demand, which the boiler transmits to the PWR_CTL
function in the form of the [StepUp] demand signal, a further boiler stage /
sequence step is enabled when the step-up delay has expired. When a boiler
reaches the stage limit, the function switches to the next boiler or boiler stage
after expiry of the switch-on delay. The last-enabled boiler stage is released to
local power control, while all other boilers are fixed at their current power
output.
If the power needs to be reduced, this is transmitted to the PWR_CTL function
via the [StepDn] demand signal. The sequence steps are then executed in
reverse order, with the defined switch-off and step-down delay times.