General Information Regarding Leak Rate Measurement Using The Msi P7-Tdx; Preparing The Leak Rate Measurement - Dräger P7-TDX Instruction Manual

Instruction Manual Dräger P7-TDX

9.3.1 General information regarding leak rate measurement using the MSI P7-TDX

The MSI P7-TDX enables determining the serviceability of gas pipelines according to
TRGI G 600 and test basis G 5952 at operating pressure. This method (comparison leak
method) is patented. The measuring device is approved by the DVGW for the serviceabil-
ity test under the registrations number DG-4805BS0029.
If all the consumers associated with the gas pipeline to be measured are closed by means
of valves, the user only needs to connect the gas pipeline to be tested to the measuring
device using a pressure measurement hose.
After the stabilization period for temperature equalization, the user is instructed to close
the gas supply (e.g. main shut-off valve directly behind the gas meter). Then, the pressure
in the gas pipeline is measured and after a time calculated by the measuring device, a
comparison leak is opened.
The leak rate and the volume of the tested gas pipeline are calculated and shown from the
measured pressure changes, with and without comparison leak.
The applied comparison leak method works independent of volume, temperature and
absolute pressure.
A possible effect on the measurement accuracy through pressure regulators, which remain
in the measuring section after closing the valve, can be prevented by selecting "leak
measurement with regulator". For this, the pipeline pressure is automatically reduced un-
der the nominal operating pressure set after closing the gas supply and measurement has
started, so that the pressure regulator fully opens and no gas can continue to flow during
the measurement. This does not affect the result of leak rate measurement.
!Observe the general requirements for handling combustible gases!

9.3.2 Preparing the leak rate measurement

Select standard leak measurement or leak measurement with
regulator in line.
The quick test and the measurement for expanded volume
are not DVGW (German competence network for all ques-
tions related to gas and water supply) tested and cannot be
stored. Depending on the stability in the gas pipeline, a quick
test can be conducted in approx. 7 minutes. The measure-
ment for expanded volume enables measuring pipelines with
up to 800 liters of volume.
Select type of gas.
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