Inficon Pernicka 700H CHLD, Translation Of The Original Operating Instructions

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helium signal falls below this setpoint, the helium is removed from the system with the
turbo molecular pump and then the measurement process is continued with the fine
leak test.
In the fine leak test, the gases escaping from the test object, except for helium, are
pumped out with the cryogenic pump. During the accumulation measurement, the
quantity of helium escaping from the test object is determined. As a result of the fine
leak test, the leak rate is calculated in the unit of measurement
[mbar l/s] or [atm cc/s] and displayed on the monitor. The test chamber is purged and
the measurement process is terminated.
The measurement process is terminated and the device is again in "Standby"
operating mode.
4.2 Operation modes
4.2.1 Operating mode Standby
Before a measurement can be started, the device must be in "Standby" operating
mode.
The device is in "Standby" operating mode:
• when the measurement process has been terminated normally after the fine leak
test;
• when the measurement process was terminated after the gross leak test;
• after a completed regeneration;
• when the device is switched on.
In the "Standby" operating mode the valves V1, V3, V4, V5, and V6 are closed. The
valve V2 is open.
During the "Standby" the test objects can be changed.
4.2.2 Operating mode measurement
If there is a leak, the tracer gas escaping from the test object is measured with the
help of a CHLD-Sensor and the leak rate is displayed as a result with the
unit [mbar l/s] or [atm cc/s].
4.2.3 Operating mode regeneration
The device has a cryogenic pump, which freezes all gases except helium and
hydrogen. The frozen gases are separated in the ice state on the inner surface of the
cryogenic pump. At regular intervals these separated gases must be evaporated in the
"regeneration" operating mode and removed from the system.