D-R 290

For continuous, contactless dust and opacity measurement at medium to high concentrations in dry flue and process gases. Also suitable for difficult plant conditions.



  • Continuous dust measurement
  • Smallest certified measuring range 0 … 15 mg/m3
  • Automatic measurement and correction of contamination
  • Automatic control functions
  • Contactless measurement
  • Maintenance and linearity check without disassembly
  • Suitable for official emission monitoring
  • Reliable measurement of medium to large dust concentrations
  • Space-saving and easy installation
  • Long life time and high availability under extreme plant conditions
  • Emission measurement of dry flue gases at the stack
  • Temperatures up to 1,000 °C
  • Corrosive flue gases, plants with complex gas matrix
  • Measurement of dry process gases


Measuring principleTransmission, contactless and in-situ measurement
Measuring variableExtinction, opacity, calibratable as dust concentration in mg/m³
Measuring rangeOpacity: Minimum 0 … 20%, maximum 0 … 100%
Extinction: Minimum 0 … 0.1, maximum 0 … 2.0
Dust concentration: Minimum 0 … 80 mg/m³, maximum 0 … 4,000 mg/m³
Certified measuring range0 … 15 mg/m³
Ambient conditionsInstallation location: Indoor or outdoor installation**
-40 … +60 °C
-30 … +60 °C (ATEX)
-20 … +60 °C (IECEx)
Operating conditions in ductTemperature: Maximum 250 °C, optional: 1,000 °C
Relative humidity: 0 … 95%, non-condensing
Relative pressure:
-50 … +20 hPa
-50 … 0 hPa (ATEX/IECEx)
Duct dimensionsInner diameter: 0.5***… 18 m
Interface*Analogue output: 1x 4 … 20 mA, maximum 400 Ohm, potential-free (various parameters adjustable)
Digital output: 2x NC/NO, maximum 60 VDC, 30 VAC, 0.5 A (various parameters adjustable)
RS 485 Modbus RTU, USB
Status display: LED
Operation and displaySoftware D-ESI 100*** or
Operating unit D ISC 100
Control functionsAutomatic zero point and reference point measurement, automatic contamination measurement and compensation
Light sourceLED, 450 … 680 nm

* Additional interfaces with D‑ISC 100 operating unit 

** Weather protection cover required for outdoor installation

*** Measuring section > 1 m


DURAG Group products and solutions under its group such as:

  • SMITSVONK (Netherlands-based) for high-energy ignition systems, pilot burners, and ignition burners
  • Hegwein GmbH (Stuttgart-based) for (gas and oil ignition burners and gas burners
  • AP2E (France-based) for ProCeas® lasercem analyzers for gas traces in hydrocarbons via infrared spectrometry online gas analysis, with no need for sample conditioning/heating
  • Grimm Aerosol Technik for detection and analysis of aerosol particles in various fields such as environmental monitoring, occupational safety and research.
  • Mercury Analysers for measuring principle that allows separate determination of elemental and oxidized mercury
  • Dust Monitors and Analysers for measure dust concentrations in dry and wet gases continuously

Approvals And Certifications

  • TÜV certificate (Germany requirement for continuous emission monitoring systems)
  • Compliant to US EPA, QAL 1 Certification, EN 14181, EN 15267, EN 16911-2
  • FM approval (ANSI safety standards)
  • Explosion Proof Certification (IECEx, ATEX, NEPSI, TIIS)
  • CE Marking (conforms with the applicable EU directive)

The DURAG GROUP is a leading provider of intelligent solutions for combustion technology, emissions and ambient air monitoring, multi-gas analysis, tunnel sensors, and environmental and process data management, with more than 70 years of experience.

The company has around 500 specialists who offer modern technology, certified instruments, and reliable services for the individual requirements of customers worldwide.

It provides a comprehensive product portfolio for industrial combustion and flame control technology, visualization and online analysis of thermal processes, gas analysis, as well as the measurement and analysis of emissions and ambient air monitoring.


D-R 290