PRESSURE LEAK DETECTOR
DLR-G ..
24/10/2018
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The pressure leak detector DLR-G monitors both walls of the double-
walled system for leaks. The monitoring pressure during operation is
higher than any pressure on the inner or outer wall, so that leaks will
be indicated by a pressure drop.
Inert gas, air from a pressure gas bottle or from a pressure gas sys-
tem can be used as leak detection media. If air is used, it must be
dried to a relative humidity of less than 10%.
The current pressure is shown on the display in mbar/bar or PSI
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:
Values of less than 150 mbar or less than 2.18 PSI will not be dis-
played.
Values of up to 990 mbar will be displayed in mbar and without
decimal.
Values from 1 bar are displayed in bar with two decimals and from
10 bar with one decimal.
Values in PSI are displayed with one or two decimals.
4.2
Normal Operating Condition
The normal operating condition is achieved during commissioning by
building up pressure to the operating pressure through the pressure
cylinder connected to the leak detector (operating mode C) or a mo-
bile pressure cylinder (operating mode I).
The existing pressure in the interstitial space is monitored with a
pressure sensor in the leak detector. Any minor leaks lead to a pres-
sure drop, which will be compensated in the operating mode C.
Depending on the grade of tightness of the entire unit, the overpres-
sure moves between the switching value Refilling OFF and the
switching value Refilling ON.
For operating mode I, the requirements for the tightness of the inter-
stitial space(s) and the connection line(s) must be set very high to as-
sure trouble-free operation for one year.
4.3
Function in Case of Leaks
If there is a leak in the inner or outer wall, gas will leak from the inter-
stitial space. The pressure drops.
When the switching value "Refilling ON" is reached in operating mode
C, refilling will be activated and the operating pressure will be built up
again. If the leakage ratio is greater than the limited refilling rate, the
pressure will continue to drop to alarm pressure.
An optical and audible alarm will be triggered when the alarm pres-
sure is reached, which will open the voltage-free contacts.
An additional relay can be used for operating mode I to establish volt-
age-free contacts when the pressure drops below the "Refilling RE-
QUIRED" pressure.
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The change of the bar and PSI settings is performed at the factory. This change can also be performed on site following
coordination with the manufacturer.
Design and Function
