HP 5971 MSD Mass Spectrometer
The HP 5971A Mass selective detector is a stand-alone capillary GC
detector designed for use with the HP 5890 A Gas chromatograph .
The base model includes:
- Cast - aluminum vacuum manifold
- Vapor diffusion high vacuum pump
- Mechanical foreline ( roughing ) pump
- Electron impact ion source
- Hyperbolic quadrupole mass filter
- Electron multiplier ( detector )
- Instrument control electronics
- Power supplies
- GC/MSD interface
Real-time control of the MSD is provided by the MSD electronics
according to setpoints and instructions from the data system. The data
system sends operating parameters to the MSD and receive status
information and data from the MSD.
The data system software includes programs to calibrate the MSD,
acquire data, and process data. It also includes utilities for file
management and editing. Tuning programs can adjust voltages in the ion
source, calibrate mass assignments, and control the scanning of the
mass analyzer. Data acquisition programs allow you to monitor the
total ion current, automatically storing the mass spectra of GC peaks
as they elute ( scanning mode ) or, alternatively, to monitor the
concentrations of particular ions ( selected ion monitoring mode ).
Dynamic range: A logarithmic preamplifier provides more than six
decades of dynamic range.
Ionization energy: 70 eV from either filament.
Mass axis stability: +/- 0.15 amu per 12 hours assuming recent
calibration, adequate ion statistics, and thermal equilibrium of the
Mass range: 1.2 - 650 amu.
Mass resolution: 0.5 +/- 0.05 amu throughout the mass range.
Scan speed: Eight user-selected scan rates with a maximum of 2000
amu/sec with 0.1 amu mass resolution.
SIM mode: In the selected ion monitoring mode (SIM) the MSD
monitors up to 20 individually selected masses at a time. Up to 200
groups of 20 masses can be selected for each run. Dwell time for each
mass is user-selectable from 10 msec to 32767 msec.
Temperature control: The GC/MSD interface temperature is
user-settable from 250° to 320° C. The end of the GC/MSD interface
conductively heats the ion source and mass filter. The vacuum manifold
is not otherwise heated.
Total ion mode: AC voltage-only mode, with adjustable low-mass
cut-off, allows the HP 5971A to operate as a non-specific,
Vacuum system: Vacuum is maintained by a vapor diffusion pump
backed by a two-stage, direct-drive mechanical pump. Overall system
pumping speed is approximately 60 liters/sec for helium. The vacuum
system can accommodate capillary flow rates up to 1ml/minute of
Size: Height - 34 cm 13.4 inches Width - 17 cm 6.7 inches Depth -
65 cm 25.6 inches Weight - 21 Kg 46 lbs excluding the external