Status & Tuning Parameters
Power
8-10
Prima PRO & Sentinel PRO Mass Spectrometers User Guide
Thermo Fisher Scientific
electrode is part of the detector assembly and is positioned between
the quad lens and the detector.
The use of two resolving slits permits the selection of a very wide
resolving slit when low mass peaks are being measured. This feature
results in the production of broad, flat-topped peaks all the way down
to mass 1.
In conventional mass spectrometers, the resolving slit size is chosen
so as to resolve adjacent peaks at the high mass end of the scale
(peaks get closer together with increasing mass). The disadvantage to
having high resolution is that low mass hydrogen and helium peaks
become very narrow and therefore prone to drift when these peaks
are to be measured.
The high resolution slit is on-axis and for peaks above the switching
point, normally greater than mass 5, the voltage for the resolution
deflector will be close to zero.
Below the switch point, the voltage will be around 250 V, for
systems with 1000 V ion energy, deflecting the beam through the
broader low resolution slit.
Note:
On the Sentinel PRO analyser, a different combination of
collector slits is used, and the switching point is typically set to mass
100. At lower masses the nominal resolution is approximately 85 and
at higher masses the nominal resolution approximately 135.
The Amp24V parameter is the 24 V PDU output for the
amplifier.
The Analyser Su24V parameter is the 24 V PDU output
analyser electronics (ASU).
The Instrument CPU 24V parameter is the 24 V PDU output for the
CPU card.
The Fan 24V parameter is the 24 V power PDU output for the air
conditioner condenser fan (safe area only). Failure can also indicate
an alarm condition within the A/C.
The Inlet Probe Current parameter is the current through the inlet
probe cartridge heater.
Power
Amp24V
Analyser
Su24V
Instrument CPU
24V
Fan 24V
Inlet Probe
Current
