Thermo Scientific Prima PRO, Руководство пользователя

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Startup & Shutdown
Procedure
7-4 Prima PRO & Sentinel PRO Mass Spectrometers User Guide Thermo Fisher Scientific
Before the filament (and ion energy) can be switched on, the pressure
in the vacuum chamber must be less than the vacuum gauge high
pressure trip level (normally set to 3.2 x 10
-5
mbar) and also higher
than the vacuum gauge low pressure trip level (1 x 10
-7
mbar).
On initial switching it is quite normal for the filament to outgas
slightly as it heats up. This will result in an increase in the measured
pressure of the vacuum system. The trip logic therefore has a limited
amount of hysteresis to accommodate the pressure rise. To prevent
the trip circuit from immediately switching the filament off again,
the “off trip” is set higher than the “on trip” so a pressure reading
above the set point is normal.
Click on the Traffic Lights button ( ) to start a scheduled
analysis. Each enabled stream will be selected according to its
sequence, the concentrations measured, and output via data
communications to an I/O unit or other host computer. If the numeric
display window is selected, the concentrations will be displayed on
the host PC monitor (
Figure 7–4 ). Similarly, if a trend display has
been configured and is selected, concentration trends with time can
be viewed (
Figure 7–5 ).
Figure 7
–4.
Numeric trend window
Vacuum Gauge
Trip Level
Starting
Scheduled
Analysis