VACUUM LEAK DETECTOR
VLXE ..
31/10/2019
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the interstitial space is evacuated until the operating underpressure
(Pump OFF) is reached.
Depending on the level of tightness and temperature fluctuation in the
overall system, the underpressure alternates between the Pump OFF
switching value and the Pump ON switching value, with short pump
running times and longer down times.
4.3 Air
leak
If an air leak occurs (in the outer wall or inner wall, above the fluid
level), the underpressure pump switches on, in order to restore the
operating underpressure. If the volume of air flowing in through the
leak exceeds the limited conveying quantity of the pump, the pump
continues to run.
Increasing leak rates lead to a further drop in underpressure (with
pump running) until the switching value “Alarm ON” is reached. Visual
and audible alarm signals are then triggered.
4.4 Liquid
leak
If there is a liquid leak, liquid penetrates the interstitial space and col-
lects at the bottom of the interstitial space.
The liquid entering lowers the underpressure, the pump is switched
on and evacuates the interstitial space(s) until the operating under-
pressure is reached. This process is repeated multiple times until the
liquid stop valve in the suction line is closed.
Due to the underpressure still existing on the measuring line side, fur-
ther fluid leaks will be sucked into the interstitial space, the measuring
line and, if appropriate, the pressure compensation vessel. This leads
to a decline in underpressure until the “Alarm OFF” pressure is
reached. Visual and audible alarm signals are then triggered.
Note: A liquid sensor connected to a magnetic valve can optionally be
used instead of a liquid stop valve. The liquid alarm is then triggered
by the liquid’s contact with the sensor.
Design and function