External Setpoint Influence (4.1.3); Setting Of Influence Function (4.1.3.2) - Grundfos Control DDD Montage- Und Betriebsanleitung

8.7.5 External setpoint influence (4.1.3)

Fig. 46 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 transmitter, or a similar transmitter. Section
parameters shows an overview of transmitter types and possible
positions.
As an example, the setpoint can be adapted to parameters that
can influence the outlet pressure 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)
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
• Discharge pressure
• External pressure
• Diff. pressure, pump
• Diff. pressure, external
• Flow rate
• Tank level, discharge side
• Tank level, suction side
• Water temperature
• Ambient temperature.
Setting via 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 8.7.6 Setting of influence function
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.

8.7.6 Setting of influence function (4.1.3.2)

Fig. 47 Setting of influence function
Description
You can select the relation between the measuring parameter
which is to influence the setpoint and the desired influence as a
9. Measuring
percentage.
The relation is set by entering values in a table with maximum
eight points by means of the operating panel.
Example:
Setpoint influence [%]
100
Fig. 48 Relation between setpoint influence and flow rate
The control unit draws straight lines between the points.
A horizontal line is drawn from the minimum value of the relevant
sensor (0 m
case from the last point to the sensor's maximum value (example
3
50 m /h).
Setting range
Two to eight points can be selected. Each point contains the
relation between the value of the parameter which is to influence
the setpoint and the influence of the value.
Setting via operating panel
• Settings > Primary controller > External setpoint influence.
1. Set the influence function.
2. Set the number of points.
3. Set: External input value (Point 1).
4. Set as a percentage: Reduce setpoint to (Point 1).
5. Repeat steps 2 to 4 for all desired parameters.
(4.1.3.2).
Factory setting
The function is disabled.
80
3
60
2
40
1
20
3
/h in the example) to the first point. This is also the
4
50
3
Flow rate [m /h]
29