Leak Rate Measurement - Dräger P7-TDX Instruction Manual

Instruction Manual Dräger P7-TDX
If the gas pipeline is airtight (does not have a leak) or if the pipeline volume is large and
the leak small (> low pressure drop), ( ) can be pressed. After an additional 60
CONTINUE
seconds, the leak rate measurement is started. In the case of "leak measurement with
regulator in line", the pipeline pressure is automatically reduced to 1 hPa (mbar) under the
nominal operating pressure set, so that the pressure regulator fully opens and no gas can
continue to flow during the measurement.

9.3.4 Leak rate measurement

After the measurement has started, the current pressure (P)
in the gas pipeline, the pressure drop (dP) calculated up to
this point and the elapsed time of the measurement period (t)
are shown.
If the pressure in the gas pipeline to be tested has dropped
by more than 0.9 hPa (mbar) or if the measurement takes
longer than 5 minutes, the internal magnetic valve is opened
and gas from the gas pipeline can flow through the compari-
son leak.
The magnetic valve is closed after the comparison measure-
ment (dP > 0.9 hPa (mbar) or t > 5 minutes) is completed.
The end of the comparison measurement is indicated acoustically. The result of the leak
rate measurement is now analyzed and shown:
The display shows the mean pressure "P", the measured leak
rate "L(t)", the leak rate with regard to the nominal operating
pressure "L(n)" and the volume "Vol" of the gas pipeline. The
volume is not shown for the "leak measurement with regulator
in line". If the leak rate is indicated with negative values, the
pressure increased in the pipeline during the measurement. If
the leak rate is smaller than -0.2 l/h or larger than 20 l/h, the
leak rates are marked with ERR and in doing so, give a warn-
ing regarding measurement errors. If the pressure dropped below 10 hPa (mbar) or 8 hPa
(mbar) during the measurement or the comparison leak measurement, "P" is marked with
ERR and the measurement is inapplicable. If the measured volume is smaller than 1 l or
larger than 300 l, the volume reading is marked with ERR because the leak rate meas-
urement can be incorrect.
The documentation menu is opened using ( ).
CONTINUE
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