Thermo Scientific Prima PRO, Руководство пользователя

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Status & Tuning Parameters
Analyser Tab
8-6 Prima PRO & Sentinel PRO Mass Spectrometers User Guide Thermo Fisher Scientific
Status Value
Magnet temp busy 8 Measuring the magnet
temperature.
Magnet failure 9 Controller or circuit failure.
Magnet pulse busy 10 Busy driving the magnet.
Magnet field init busy 11 Initialising the system (about 60
s)
The approximate magnetic field setting, in Tesla, is indicated by the
Mass Filter parameter. The value for Mass 28 with 1000 V ion
energy is typically 0.4 Tesla.
The relationship between mass and magnetic field and ion energy is
given by:
Mass

(magnetic field)
2
/ion energy
A four times increase in magnetic field strength therefore doubles the
mass detected.
At pressures above the value set in the Pressure Set Point parameter,
power is removed from the filament supply, source heater, SEM
supply, and source high voltage supplies to protect the analyser from
damage which may result if run at high pressure.
The System Pressure value indicates the pressure as reported by a
Penning vacuum gauge head that is mounted on the top right of the
vacuum chamber and is a measure of the high vacuum produced by
the turbo molecular pump.
The pressure, as measured by the Penning gauge, is a combination of
the amount of sample gas leaking into the chamber via the capillary /
leak arrangement and gas that ‘evolves’ from the internal surfaces of
the vacuum system. This is known as out-gassing.
When the inlet is blocked, the vacuum falls to its background level,
which is usually in the region of 10
-7
mbar. When the inlet is open,
the operating vacuum should be in the region of 1 - 10 x 10
-6
mbar.
This varies slightly from instrument to instrument and on the gas
being sampled.
The upper limit of pressure that can be displayed by the Penning
gauge is about 1 x 10
-2
mbar. A stable reading at this level indicates
that the pressure may be too high to be measured by the gauge and
that there is either a significant system leak or a pumping fault.
Check that the turbo molecular pump is up to speed (indicated as
Turbo Revs on the Instrument Status window). Check that the rotary
pump is functioning correctly.
Mass Filter
Pressure Set
Point
System Pressure