Gas Analysis Systems
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Vacuum Systems and Complete Gas Analysis Systems.

The COMPASS concept is to provide complete solutions to gas analysis problems. With a wide choice of inlet systems, vacuum systems, ion sources and flexible software, Compass can be easily configured to your application. 

Key Benefits

bulletFully Enclosed
bulletChoice of pumping configurations
bulletFully interlocked, 

Mass Spectrometers by their very nature require a high vacuum environment to operate. This is provided by a High Vacuum System. Gas that requires analysis is then leaked into the high vacuum system at a controlled rate by the Inlet System. There is no such thing as a perfect vacuum. Residual Gases are always present. These residual gases may interfere with the gases that require measurement therefore it is important that these residual gases are kept to a minimum. The better the vacuum the lower the residual gases.

The Main High Vacuum System.

Most ASI mass spectrometers are small and therefore only require a small vacuum housing. The amount of gas required for analysis that will be leaked into the quadrupole Ion Source is also very small, therefore  for the majority of gas analysis applications the main high vacuum pump can be satisfied by a small turbo-molecular pump. A small rotary vane pump will provide the low backing pressure for the turbo-pump.

Therefore a typical high vacuum system will normally contain the following items.

1. Fully enclosed Cabinet (Floor standing or Bench Top) with Fan cooling.

2. Mass Spectrometer housing with ports for inlet system and high vacuum gauge.

3. Turbo-molecular pump with splinter shield..

4. Backing Pump

5. Anti-vibration mountings for the pumps.

6. Main switch panel and fuses.


The following additional items form a Complete Gas Analysis System.


7. Second Pump for inlet system

8. Inlet system.

9. Fitting of High and low vacuum gauges. with power supply .

10. Mass Spectrometer, control electronics and power supply.

11. Additional wiring to provide interlocking between the pumps gauges and mass spectrometer for 'Fail Safe Operation'.

Compass vacuum systems are configured for each application.


In order to interface the low pressure requirement of the mass spectrometer to the environment of the 'real-world' and hence cater for a wide range of analyses, Compass includes a choice of inlet systems from simple leak valves to computer controlled multi-stream gas samplers. Many inlet systems are specifically designed to meet particular requirements.

Further information on choice of  inlet systems.


Gas Analysis Systems:-

Compass vacuum systems are configured for each application. The selection of turbo-molecular pump, Backing pump  and control/monitoring equipment is made easier by relying on the wealth of experience of Larimax vacuum engineers. High and Low vacuum gauges are normally fitted as standard to provide system interlocking for Fail Safe operation.

 < Floor Standing System.

Complete gas analysis system in fully enclosed mobile cabinet.


Compact Bench-Top System. Complete with High Vacuum system, Capillary inlet for atmospheric sampling, Quadrupole and electronics

Portable Gas Analysis Systems. (Battery only or Battery/Mains)

ASI now offer complete portable gas analysis systems for field use. They are based on dry turbo vacuum systems with diaphragm pumps that consume very low power. These normally run on 24V and the total power requirements including the mass spectrometer is typically 60Watts after start up. The only complete portable mass spec system that will operate from a  a light weight 24V 22Ah rechargeable battery pack that will run the system continuously for a full 8 hours.

These systems measuring from 20cm x 33 cm x 42cm can be easily carried by a single person and weigh from approx 15Kg depending on options chosen. The Lithium battery pack weighs approx 3 Kg and can be built in if required

For details Click on TGA-200 on the product list




Contact Information

+44 (0)1805 625 205
Postal address
  Anglo Scientific Instruments,
  3, Devon Units, Hatchmoor Industrial Estate,
            Torrington, Devon. EX38 7HP. UK.
Electronic mail

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