6
4 Function
4.1 Processing of the measured signals
• The unit displays the current system pressure�
• It generates 2 output signals according to the parameter setting�
OUT1
• Switching signal for system pressure limit value�
OUT2
2 options
• Switching signal for system pressure limit value�
• Diagnostic signal (output 1 is inactive in case of a fault)�
4.2 Switching function
OUTx changes its switching state if it is above or below the set switching limits
(SPx, rPx)� The following switching functions can be selected:
•
Hysteresis function / normally open: [OUx] = [Hno] (→ fig. 1).
•
Hysteresis function / normally closed: [OUx] = [Hnc] (→ fig. 1).
First the set point (SPx) is set, then the reset point (rPx) with the requested
difference�
•
Window function / normally open: [OUx] = [Fno] (→ fig. 2).
•
Window function / normally closed: [OUx] = [Fnc] (→ fig. 2).
The width of the window can be set by means of the difference between SPx and
rPx� SPx = upper value, rPx = lower value�
1
2
P = system pressure; HY = hysteresis; FE = window
