Pfeiffer ASM 340 - Advanced Settings: Leak Detection and I;O; Leak Detection Parameters: Timer, Suppression, Pressures, Calibration

Advanced settings
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7.8.1 Leak Detection Menu
 From the "Settings" screen, press [Advanced][Leak Detection].
7.8.2 Leak Detection: Start-up timer
The start-up timer prevents the leak detector from being used for a pre-determined du-
ration after it has been switched on. This means measurements cannot be made until the
leak detector is thermically stabilized, or while traces of tracer gas remain in the detector.
7.8.3 Leak detection: Background suppression
This function is used to suppress the detector's background.
Note: after calibration, with background suppression function activated, the leak detec-
tor's background will be lower than 5 · 10
-13
Pa·m
3
/s (5 · 10
-12
mbar·l/s).
7.8.4 Leak Detection: Crossover Pressures
In a hard vacuum test, used to define the crossover pressures in the different test modes.
7.8.5 Leak Detection: Calibration
From the "Settings" screen, press [Advanced][Leak Detection].
Start-up timer  Set the start-up timer.
From the "Settings" screen, press [Advanced] [Leak Detection] [Background Supp.].
Activation  Activate the function (’on’ if activated).
This function is recommended for testing very small leaks, which improves mea-
surement and reading.
This function can be used to measure a leak rate 2 decades lower than the detec-
tor's background, when the detector is no longer in roughing.
From the "Settings" screen, press [Advanced] [Leak Detection] [Crossover pressures].
Gross Leak  Set the cross over from Roughing to Gross Leak mode.
Normal  Set the cross over from Gross Leak mode to Normal mode.
NOTICE
Detector calibration
When switched on, the detector suggests that the operator carry out an auto-calibration
(if calibration parameter = operator). For the optimal use of the detector, this auto-ca-
libration must be performed. In all situations, a manual or automatic calibration must
be performed:
● at least once a day
● to optimise the measurement reliability for high sensitivity tests
● if it is uncertain whether the detector is working properly
● during intense and continuous operation: start an internal calibration at the beginning
of each work session (e.g. work in teams, every 8 hours).