1. according EU Standard EN 13160-2
Class I Leak Detection Systems - Highest level of monitoring and prevention of double walled tanks and pipes,
according EU Standard EN
Vacuum systems
working principle…

2. Vacuum leak detector (e.g. THOMAS-ASF IIIF)
Leak Detection acc. EN Class I Working principle - Vacuum system
Vacuum leak detector (e.g. THOMAS-ASF IIIF)
Green operation light
Normal Operation
- Leak detector shows normal operation by green light
Suction line
Measuring line
- Interstitial space of the double walled tank (or pipe) is evacuated up to system setup „Pump OFF“
OFF ON
Pump
Vacuum in the Interstitial
Air flow
- Normal pressure differences, caused by the system or temperature changes balanced by the pump
Interstitial space
Note:
If the starting frequency of the pump increasing more and more, this points to an increasing leakage.
OFF ON
Double walled tank (or pipe)

3. Leak Detection acc. EN 13160 Class I Working principle - Vacuum system
Vacuum leak detector (e.g. THOMAS-ASF IIIF)
Red alarm light
Leakage in the system…  Air leakage
Alarm buzzer switch Buzzer disabled indicated by yellow light
- Air is sucked through the inner (or outer) wall into the interstitial  called air leakage
- Vacuum level in the interstitial space drops
Vacuum in the Interstitial
Pump
Air flow
- At set point “Pump ON”, pump starts
- For a higher leakage, the pump can‘t balance, the vacuum level changes down to the set point “Alarm ON”
… inner tank wall, above the liquid level
- Alarm situation indicated by visual red light and acoustic buzzer
- Switch off the buzzer, call for service
OFF
OFF ON ON
… in the outer tank wall or

4. Leak Detection acc. EN 13160 Class I Working principle - Vacuum system
Vacuum leak detector (e.g. THOMAS-ASF IIIF)
Leakage in the system…  Liquid sucked into the interstitial
- Liquid is sucked through the wall into the interstitial
- Liquid volume in the interstitial is slowly increasing
- Vacuum level drops because of decreasing air volume
Vacuum in the Interstitial
Pump
Air flow
… inner tank wall, below the liquid level
OFF
OFF ON

5. Leak Detection acc. EN 13160 Class I Working principle - Vacuum system
Vacuum leak detector (e.g. THOMAS-ASF IIIF)
Leakage in the system…  Liquid sucked into the interstitial
- Liqiud is sucked through the wall into the interstitial
- Liquid volume in the interstitial is slowly increasing
- Vacuum level drops because of decreasing air volume
Vacuum in the Interstitial
Pump
Air flow
- At set point “Pump ON”, pump starts
- The interstitial will be filled with liquid step by step
OFF
OFF ON ON

6. Leak Detection acc. EN 13160 Class I Working principle - Vacuum system
Vacuum leak detector (e.g. THOMAS-ASF IIIF)
Leakage in the system…  liquid barrier closes
- On the tank top, liquid is sucked into the suction line
- Liquid barrier filled up and closes
- Connection suction line to the interstitial and measuring line blocked
Vacuum in the Interstitial
Pump
Air flow
OFF ON ON

7. Leak Detection acc. EN 13160 Class I Working principle - Vacuum system
Vacuum leak detector (e.g. THOMAS-ASF IIIF)
Red alarm light
Leakage in the system…  Alarm indication
Alarm buzzer switch Buzzer disabled indicated by yellow light
Remainimg vacuum in the measuring line will absorb liquid, Vacuum level decreases
- At set point “Alarm ON”, Alarm situation indicated by visual red light and acoustic buzzer
Vacuum in the Interstitial
Pump
Air flow
- Switch off the buzzer, call for service
- The vacuum level in the measuring and suction line will keep the liquid in the interstitial space for a certain period of time  preventing leaking into the environment
OFF ON ON

8. Präsentation neuer LAG Newsletter.ppt
Focus on Safety,
For A Clean Environment.
Proven ASF Leak Detector Technology
Contact
Mail:
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Copyright – Gardner Denver Thomas GmbH, D Puchheim, 02/2014
Thomas does not warrant, guarantee or assume any obligation or liability in connection with this information.
Präsentation neuer LAG Newsletter.ppt