Details on Technical Data for Differential Pressure Closed-loop Controller
Information on the technical data dialog for differential pressure closed-loop controller.
A differential pressure closed-loop controller is installed for keeping a constant differential pressure (within a proportional band required by the controlling system) in a pipe run. For this purpose, you may specify certain settings of the differential pressure closed-loop controller for calculation in the dialog shown below. Differential pressure closed-loop controller always consist of two components, one of which is drawn into the supply and one of which is drawn into the return.
The two components of the differential pressure closed-loop controller have to be assigned to each other again after copying. By using the Connect components < command, you have the option to select the two copied components one after the other and to reassign them thus.
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Name
Specifies the name of the component. You can modify the name. Clicking 
restores the default setting.
Design data (secondary side)
In the upper part of the dialog box, the maximum pressure loss of the secondary side of the differential pressure closed-loop controller is displayed.
Valve data
Select valve...: By using the Select valve button you can select a manufacturer-specific differential pressure closed-loop controller which you can assign to the selected component via the Apply button afterwards. The selected differential pressure transducer with appertaining specific data will be displayed in the dialog after selection. The range of available differential pressure closed-loop controllers depends on the installed manufacturer data sets. Further valves can be read in via VDI3805 interface in the Select armature series dialog.
Reset: The Reset button resets the manually assigned armature to a neutral model.
Info...: Opens the dialog Information about this valve with further values and information stored in the data set.
Nominal diameter
In this drop-down list the current nominal diameter of the valve is displayed. You can then select a dimension. You can fix this dimension by activating the checkbox fixed. The set nominal diameter will be used for the calculation. By selecting the option free in the drop-down list, you leave the dimensioning to the program, which then assigns the nominal size based on the calculation results. The new nominal diameter selected by the program will subsequently be displayed when you open the dialog the next time.
Further data: The current values for mass flow rate, pressure loss, and the valve setting are displayed here.
Setting
The required set value must be greater than or equal to the maximum pressure loss of the control circuit with regard to the nominal or dimensioned volume flow of the differential pressure closed-loop controller. In case the set value is greater than the maximum pressure loss, the pipe network of the subsequent control circuit is required to reduce the excess pressure at the control valves designed for this purpose, so that the dimensioned volume flow can set. In case the set value is smaller than the calculated pressure loss of the most unfavorable control circuit on the secondary side, an error message will be displayed (in the Reports) during calculation. You may further set the P-deviation (due to the proportional regulation property of the differential pressure closed-loop controller) and the cv value of the open controller in the lower part of the dialog box. The corresponding values can be found in the documentation of the selected manufacturer.
Valve pressure loss
Shows the pressure loss of the valve in the current trade.
Installation example for differential pressure closed-loop controller
