A vacuum (underpressure) is generated in the interstitial space.
Untightnesses lead to a vacuum loss, which can be compensated to a small extent by integrated pumps to ensure trouble-free operation.
Relevant leaks lead reliably to an optical and acoustic alarm.
The tank design, the height of the tank and the density of the stored goods determine the underpressure to be applied.
Minimum alarm pressure (mbar) = 30 mbar + tank height (cm) * density (g/cm3) * 0,98
(for underground tanks: density at least 1 g/cm3)
(for flat bottom tanks: minimum alarm pressure 255 mbar)
(for tanks with a suction line to the low point of the interstitial space: minimum alarm pressure 34 mbar)
The alarm pressure is given in mbar in the type designation, e.g. VL 330.
The operating pressures are higher than the respective alarm pressures. The tank's interstitial space must withstand these underpressures.
Vacuum leak detector for one underground or one aboveground tank. For wall mounting.
A standard at heating oil storage tanks, diesel tank farms and in a suitable durable design for tank farms for chemically aggressive liquids.
The requirements of the respective documentation must be observed!
Equipment that can come into contact with stored goods or their vapors must be made sufficiently durable (e.g. connection lines in the manhole chamber).
VL leak detectors must neither be installed in Ex areas nor come into contact with explosive vapor-air mixtures.