MultiGas Infrared Module NDIR

  • NDIR Sensor = non-dispersive infrared sensor
  • Featuring high-performance light-emitting diodes (IR-LED) and thermal micro-radiators


CO2 CO N2O CH4 CnHm* CF4 SF6 H2O

The RITTER MultiGas Sensors NDIR Module (non-dispersive IR sensor) has been specially developed for use in high-quality gas analysis. In the design phase special emphasis was placed on high stability and a low detection limit. These goals could be fully achieved by using high-performance light-emitting diodes (IR-LED) and thermal micro-radiators which were adapted to the requirements of gas detection. In the spectral range from 2 μm to 12 μm, carbon dioxide, carbon monoxide, hydrocarbons, water vapor and sulfur hexafluoride can be safely detected down to the ppm range with this innovative sensor platform.

The various photometric components such as detectors, emitters, measuring sample cell, etc. will be assembled user-specifically in a high-quality tabletop casing by RITTER.
RITTER MultiGas Sensorgehäuse


  • Biogas research
  • Environmental and process measuring technology
  • Elemental analysis
  • TOC-analyzers
  • Industrial gas analysis
  • Natural gas analysis

Characteristics and Benefits

  • Group of detectable gases:
    CO2 CO N2O CH4 CnHm* CF4 SF6 H2O
  • Measurement technology: NDIR-Sensor (non-dispersive IR sensor)
  • Measurement accuracy ±2% of Full Scale (F.S.)
  • No cross-sensitivity to H2
  • Operating temperature: 5 – 45 °C
  • Operating pressure: 800 – 1200 mbar (hPa) abs.
  • Flow rate range: 1 ltr/day – 100 ltr/h
  • Warm-up time: 2 min
  • Response time (t90): ≈ 3 sec
  • Interface USB, on request RS 232
  • Sensor cuvette: Aluminum, gold plated for sensor length 100 ≥ mm
  • Incl. temperature compensation
  • Incl. data acquisition software
  • In tabletop casing, overall dimensions W x H x L 171 x 85 x 246 mm, weight approx. 1,9 kg
  • Gas connection: PVDF screw-type tube connection for tube Øi 4 mm, Øa 6 mm
  • Power supply: 24 VDC (incl. power plug 100 – 240 VAC / 24 VDC)


  • Readjustment of the zero-point is recommended once a week.
  • Contamination of the measuring cuvette can lead to shifting of the end-point. Due to the integrated filter, re-adjustment of the end-point is generally not required – but can be performed once a year.
  • Additionally, cartridges filled with an inert and the respective test gas for recalibration of the zero and end-point can be provided.
  • Long-term drift is < 1% of Full Scale (F.S.) / 24 h.

Options / Additional Sensors

Oxygen Sensor

Overview The oxygen sensor is a sensor module available as option in addition to a RITTER MultiGas NDIR or NDUV sensor. The measured oxygen concentration is displayed in the provided …

Pressure Sensor

Overview A change in gas pressure causes a change in the number of molecules per volume and thus a change in gas density. This density change in turn has a …

Humidity sensor

The humidity sensor is a sensor module available as option in addition to a RITTER MultiGas NDIR or NDUV sensor. The measured humidity values (absolute and relative) are displayed in …

Analog Voltage Output

Overview For connection to an analog data acquisition device the analog voltage output port (located at the rear side of the sensor casing) provides alternatively the following voltage levels: 0 …

V 1.0 / Rev. 2022-07-24 / Subject to alterations.