LEYBOLD 250000, Руководство по эксплуатации

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Head
81
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GA10218_0101 - 5/2002
6.6.7.3 Maximum evacuation time
Main menu > Settings > Monitoring functions > Maximum evacuation
time
This menu item is used to define when the gross leak message is to
occur. The gross leak detection process operates in two steps and the
limits can be adapted as required.
This menu item is particularly useful in series testing under the same con-
ditions at all times.
After pressing the start button the test sample is evacuated. If the pres-
sure conditions (p1 < 100 mbar) are not attained, or if the pressure does
not drop low enough within the periods of time specified here, the pump-
down process is terminated and the display will indicate a message (see
8.2, W75 and W76).
The periods which are selected in each case depend firstly on the desired
reaction time for the gross leak message, and secondly on the volume of
the test sample and the effective pumping speed.
Caution: If the evacuation time was set to endless, the oil level of the
mechanical pump should be checked more often.
Softkey No. 2:
↓
Decreasing maximum evacuation time until p1 < 100 mbar. Within this
period of time the inlet pressure at the test flange must have dropped
below 100 mbar. The duration may be selected freely between 1 second
and 9 minutes or can be set to endless. The default is 30 seconds.
Softkey No. 3:
↓
Decreasing maximum time until measurement Within the period of this
time the status of measurement readiness must have been attained, i.e.
the inlet pressure must have dropped below 15 mbar. The duration may
be freely selected between 5 seconds and 30 minutes or can be set to
endless.
Softkey No. 5: ?
Help text
Softkey No. 6:
↑
Increasing maximum evacuation time until p1 < 100 mbar
Softkey No. 7
↑
Increasing maximum time until measurement.