106
Auxiliary functions
26.2.2. CUTOFF – Sealing function
This function causes the valve to be sealed outside the control area.
This is where you input the limits for the position set-point value (CMD) as a percentage, from which the actuator
is fully deaerated or aerated.
Controlled operation opens or resumes at a hysteresis of 1 %.
If the process valve is in the sealing area, the message „CUTOFF ACTIVE“ is indicated on the display.
Only for type 8793: Here you can select the set-point value to which the sealing function is to apply:
Type PCO
Process set-point value (SP)
Type XCO
Position set-point value (CMD)
If Type PCO was selected, the limits for the process set-point value (SP) are input as a percentage with ref-
erence to the scaling range.
Factory setting: Min = 0 %; Max = 100 %; CUT type = Type PCO
Enter
value
Enter
value
Sealing threshold
Deaeration (0 = not active)
Adjustment range:
0 ... 25 %
Sealing threshold
Aeration (100 = not active)
Adjustment range:
75 ... 100 %
EXIT
*
OK
CUTOFF
Min 0 %
Max 100 %
CUT type Type PCO
Type XCO
ENTER INPUT
INPUT
INPUT
Available for Type 8793 only
SELEC
SELEC
Select process
set-point value
Select position
set-point value
EXIT
* If the submenu is left by pressing the
ESC
key, the value remains unchanged.
Figure 55: Operating structure CUTOFF
The changed data is saved in the memory (EEPROM) only when there is a switch to the process level,
by leaving the main menu (MAIN) using the left selection key
EXIT
. During the save process, the save
symbol is indicated
on the display.