8.7.5 External setpoint influence (4.1.3)
Fig. 40 External setpoint influence
Description
The function allows you to adapt the setpoint by letting measuring
parameters influence the setpoint. Typically an analog signal from
a flow or temperature transmitter, or a similar transmitter. For an
overview of transmitter types and possible positions, see
installation and operating instructions for Control MPC.
As an example, the setpoint can be adapted to parameters that
can influence the outlet pressure or temperature of the system.
The parameters which influence the performance of the system
are shown as a percentage from 0 to 100 %. They can only
reduce the setpoint, as the influence as a percentage divided with
100 is multiplied with the setpoint:
Actual setpoint (SP) = selected setpoint x influence (1) x
influence (2) x etc.
The influence values can be set individually.
A low-pass filter ensures smoothing of the measured value which
influences the setpoint. This results in stable setpoint changes.
Setting range
•
0-100 % signal
•
Inlet pressure
•
Outlet pressure
•
External pressure
•
Diff. pressure, external
•
Diff. pressure, pump
•
Flow rate
•
Tank level, outlet side
•
Tank level, suction side
•
Return-pipe temp., external
•
Flow-pipe temperature
•
Return-pipe temperature
•
Differential temperature
•
Ambient temperature
•
Differential temperature.
Setting via the operating panel
•
Settings > Primary controller > External setpoint influence >
Input value to be influenced by. A list of available parameters
appears.
1. Select the parameter which is to influence the setpoint.
2. Press [Back].
3. Set the influence function. See section
influence function
(4.1.3.2).
4. Set the number of points.
5. Set: External input value (Point 1).
6. Set as a percentage: Reduce setpoint to (Point 1).
7. Repeat steps 4 to 6 for all desired parameters.
8. Press [Back].
9. Set as seconds: Filter time.
10. Select: Enabled.
Factory setting
The function is disabled.
If the Multisensor function is enabled, it will have a
higher priority than the External setpoint influence
which will be overruled.
8.7.6 Setting of
33