LEYBOLD DISPLAY THREE, Инструкция по эксплуатации

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GA09037_002_C0
– 09/2016
29
Figure 18
–
Behaviour of a switching function in
response to pressure changes
p
Pressure
t Time
NO Normally open contact
COM Common contact
NC
Normally closed contact
The range between the lower and the upper threshold value produces a certain amount of
hysteresis between switching on and switching off of the relay. The hysterisis prevents rapid
switching on and off of the switching function when the pressure is close to a switching
threshold.
7.1.2 Configuring the Switching Functions

Select the desired measurement channel by operating the pushbutton CH several
times.

Keep the pushbutton PARA depressed for approximately 2 seconds.
The instrument is now running the parameter mode in the parameter group SP.

Press the pushbutton PARA to select the desired parameter.
The name and the value of the parameter are displayed.

Use the arrow pushbuttons so as to change the threshold value.
The value of the parameter is changed.

Repeat the steps to change further parameters of the parameter group.
7.1.3 Adjustment Range
The upper and the lower threshold value can be changed depending on the type of sensor
in the range between 1·10
3
and 1·10
-12
mbar.
Hysteresis amounts to at least 10% of the lower threshold value.
CAUTION:
Select the threshold values only within the range of the selected sensor.
CAUTION:
The threshold values have to be adjusted when the sensor type on a
measuring channel has been changed.