The HP 5971A Mass Selective Detector is a stand-alone, capillary GC detector designed for use with the HP 5890A Gas Chromatography (GC). 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 with suitable software includes to calibrate ( tune ) 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 ).

HP 5971 MSD Specifications:

• Dynamic range: A logarithmic preamplifier provides more than six decades of dynamic range.
• Ionization energy: 70 eV from either filament
• 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 (SIM) mode, the MSD monitors up to 20 individually selected masses at one time. Up to 200 groups of 20 masses can be selected from 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°C 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, high-sensitivity detector.
• 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 ( atmosphere ) of helium.

The HP 5890 Series II GC provides flexibility in choices among inlets, columns, and detectors through the use of liners and adapters, allowing any standard column to be used without sacrificing performance. Additional flexibility is gained through positions of inlets and detectors relative to each other and through the large internal volume of the oven. There are five inlet options and six detector, as well as a wide variety of flow and pressure control components.

In gas chromatography (GC), a moving gas (the mobile phase) carries the sample across a stationary phase (the solid support found within a GC column). It is estimated that 10-20% of the known compounds can be analyzed by GC. To be suitable for GC analysis, a compound must have sufficient volatility and thermal stability. GC is normally used when the sample can be vaporized below 400-450°C.

The HP 5890 Series II GC Specifications:

• Heated Devices
  • Five heated zones standard: Two detectors, Two inlets, one auxiliary
  • Methods stored: Two
• Split/Splitless Capillary
  • Range to 400°C in 1°C increments
  • Back-pressure design permits independent adjustment of split flow rate without affecting column flow
  • Septum purge built in at 3 ml/min
  • Accepts columns up to 1.2-mm od
  • Multimode design includes split and splitless injection
  • Splitless purge time variable in 0.01-min elements
• Column Oven
  • Operating range: 4 °C above ambient to 450 °C
  • Setpoint entry: 1 °C for temperatures, 0.1 °C for program rates
  • Programming: Rates 0.1 to 70 °C per min, 650 min maximum run time, Three ramps with initial/final holds

This refurbished HP 5971A comes with heater transfer line, HP 5890 II GC with ECD, Suitable Software, PC, all necessary HPIB cables, Edward Vacuum Pump. It is really in a great shape and tested at SpectraLab Scientific. A 90-day warranty is included. Multiple available.