Technical Description: Inlet
Solenoid Inlet
C-28
Prima PRO & Sentinel PRO Mass Spectrometers User Guide
Thermo Fisher Scientific
Table C
–2.
Solenoid inlet system specification
Number of inlets (sample)
1 or 6 (options)
Number of inlet (calibration)
6 (standard)
Sample / calibration gas filtration
requirement
2 µm
(1)
Sample gas inlet flow rate (regulated
externally)
0.1 to 2.0 l/min
Sample gas inlet pressure. Maximum,
exhaust blocked to give above typical
flow.
0.2 bar(g)
(2)
< 0.1 bar
(3)
Maximum sample gas / line
temperature
60°C
Calibration gas flow (regulated
externally)
0.1 to 0.25 l/min
Calibration gas pressure
0.5 to 2.0 bar(g)
Exhaust requirements
Pressure range: 0.8 - 1.2 bar(g)
Stability: ±3 mbar/min
Gas connection
1/4” or 6 mm
Solenoid valve drive
24 Vdc, 7 W
Flushing time required (t
99.9%
decay
time)
Sample inlet (1 inlet option): 5
seconds
Sample inlet (6 inlet option): 20
seconds
Calibration inlet: 45 seconds
Notes:
1
Gas must be free from liquids or materials that will condense at the operating
temperature of the inlet.
2
Limit is to prevent over-pressurisation of the mass spectrometer.
3
Pressure relative to exhaust pressure.
Refer to
The principle element of the inlet is the micro capillary block
assembly that incorporates a 3/2 selector valve, micro capillary, and
flow sensor. The 3/2 valve selects gas from either the sample inlet
section or the calibration inlet section, to flow across the micro
capillary and through the flow sensor.
In the six inlet stream configuration a six-way manifold of 3/2
solenoid valves provides sample stream selection, sample gases
being connected directly to ports on this manifold. The normally
open ports of all six valves are connected to a common exhaust that
provides for continuous flow of sample even when not selected.
Inlet Operation
