Residual Gas Analyzer

Residual Gas Analyzer

The Extrel  Residual Gas Analyzer RGA is a reliable, easy-to-use residual gas analyzer that includes full range pressure measurement. It is the best performing RGA at an affordable price, which makes the system an ideal choice for background gas analysis, leak detection and vacuum chamber characterization. 

The Extrel RGA is available in two (2) mass ranges, 1 to 100 amu or 1 to 300 amu. The system comes standard with a Faraday detector or an optional dual Faraday/Electronic multiplier detector. 

The Extrel RGA utilizes RS-232C or USB communication with Windows® XP or 7 operating systems. The software is powerful and easy to use. 

The RGA100 and RGA300 are the ultimate RGA measurement probes. A single device, mounted on a 2-3/4” inch flange, contains a Pirani gauge, an ion gauge, and a quadrupole mass analyzer. An intelligent start-up design allows for the system to know when to switch from the Pirani to the ion gauge, and finally to the quadrupole system. All Extrel models start at 1 amu. The RGA100 goes to 100 amu and the RGA300 goes to 300 amu. 

Long-Life Dual Filaments and the Ion Source Kits 

Dual thoria-coated filaments are used for electron emission for both the quadrupole and ion gauge operation. The filaments are protected against stress from vacuum excursions by both the ion and the Pirani functions. Our RGA will outlast filaments in conventional RGA units. When a filament eventually does burn out, the second filament will allow for normal operation until filaments are replaced.

Ultra-Sensitive Detection 

The RGA units come standard with a Faraday cup detection system. With the Faraday cup alone, the partial pressure measurements from 10-4 and 10-11 torr may be made. With the multiplier option, this sensitivity is extended down to 5 x 10-14 torr. The novel ion current amplifier detects ion currents from 10-6 to 10-15 amps in a single scan. This huge dynamic range allows for very large and very small peaks to coexist on one scan. 


Mass Range

  • RGA100(M) 1 to 100 amu RGA300(M) 1 to 300 amu 

Mass Filter Type

  • Quadrupole 

Detector Type

  • Faraday cup 


  • Greater than 0.5 amu at 10% peak height. Adjustable to Constant peak width throughout the mass range. 

Sensitivity (A/Torr)

  • 5×10-4 into Faraday cup measured with N2 at 28 amu with 1 amu full peak width, 10% height, 70 eV electron energy, 6 eV ion energy and 2 mA electron emission current. Multiplier operation adds a factor of about 1000. 

Minimum Detectable Partial Pressure:

  • 10-11 torr measured with N2 at 28 amu with 1 amu full peak width, 10% height, 70 eV electron energy, 6 eV ion energy, and 2 mA electron emission current. With multiplier this detection is to 5 x 10-14 torr. 

Operating Pressure

  • Atmosphere to UHV (ion gauge operation below 10-1 torr and RGA operation below 10- 4 torr) 

Maximum Operating Temperature

  • 50°C 

Bakeout Temperature

  • 300°C (without CCU) 

Total Pressure Measurement

  • Available in Pirani, BA, and RGA modes 

Ionizer Design

  • Open ion source, electron impact ionization 

Prove Materials

  • SS304, Kovar, Tungsten, Alumina, Iridium, Copper, Nickel 


  • Dual thoria-coated iridium with firmware protection. Built-in 1 to 30 W degas ramp-up. Engineered for field replacement 

Electron Energy

  • 40 to 150 V, programmable 

Ion Energy

  • 3 to 10 V, programmable 

Electron Emission Current

  • 0.2 to 5 mA, programmable Probe Dimension: 6.7” from flange face to top of ionizer 

CCU Extension

  • 5.5” from flange face 

Minimum Tube I.D.

  • 1.375” Probe Mounting 


  • 2.75” CF 

CCU Dimensions

  • 3.3” x 4.8”x 7.5”. Easily separated from the probe for bakeout 

Warm-up Time

  • Mass stability ±0.1 amu after 30 minutes 

Computer Interface

  • RS-232C, up to 115,200 Baud Software Windows® NT, 2000, XP based application. Requires Pentium or better 

Power Requirement

  • 24 VDC @ 2.5 Amps. Standard 120/240 VAC adapter supplied 


  • 5 lb

Questions? We’re here to help.

Extrel CMS, LLC 
575 Epsilon Drive
Pittsburgh, PA 15238

Members of Process Insights, Inc.

Copyright © 2022 Process Insights, Inc. 
All Rights Reserved.