D-R 290

Optical dust and opacity monitor

Certified optical transmission monitor to measure the opacity or dust concentration of sample gas. Suitable for plants which require the monitoring of dust missions by law. Two freely configurable analogue outputs allow monitoring of opacity and dust concentration values at the same time.


  • Suitable for systems with variable gas speed
  • Allows calibration to measure the dust concentration in mg/m3
  • Measures opacity and/or optical density
  • Can be used even at thick-walled stone / insulated ducts
  • Device is not in contact with sample gas
  • Automatic zero and reference point check
  • Automatic measurement and correction of soiling of optical windows
  • Super-wide band diode (SWBD), long life, reduced influence of variable particle sizes
  • Hermetically sealed enclosures - no flue gas diffusion to optics or electronics unit
  • Optimized purge air reduces pollution, provides long maintenance intervals
  • Heated optical window
  • Easy installation, adjustment and maintenance, no PC required
  • Local control unit displays opacity, extinction or mg/m3 values
  • Additional display unit as an option in up to 1000m distance
  • Automatic range switching output


Suitable for dust concentration measurement

  • at incinerators in general
  • at installations in accordance with 2000/76/EC WID / 17 BImschV
  • at garbage, hazardous waste and sewage sludge incinerators,
  • at facilities for cement production
  • at installations in accordance with 2001/80/EC LCPD / 13 BImschV / Clean Air Act
  • at power stations with gas, oil, coal or co-firing
  • at converter plants and asphalt mixing plants
  • at installations for the incineration of biomass
  • at facilities pursuant to 27th BImschV


Suitable for measuring the opacity of flue gas

  • at equipment in accordance with U.S. EPA 40 CFR 60 PS1, special MCOC required
  • at cruise and container ships


Suitable for measurement of dust load in warehouses

Technical Data

Sample gas typeAir, flue gas, non flammable process gas
Sample gas temperatureAbove due point,
-25...250 °C (-13…482 °F) standard
-25...1000 °C (-13...1832 °F) option
Inner duct pressure-50...+20 hPa (optional higher)
Sample gas relative humidity0...95% RF, non-condensing
Stack/duct inner diameter1…18 m (3.3…59.1 ft)
Measuring principleMeasuring the optical transmission of visible light which passed a measuring path twice.
Conformities2000/76/EG WID / 17. BImschV
2001/80/EG LCPD / 13. BImschV
27. BImschV
EN 13284-2, EN 14181
EN 15267-3
40 CFR 60 US EPA PS1
40 CFR 60 US EPA PS11
CertificatesCE, COC QAL1 DIN EN 14181 / DIN EN ISO 14956 / EN 15267-3, MCERTS, Pattern Approval GOST R, Pattern Approval certificate Rep.of Belarus, Pattern Approval Certificate PRC, MCOC 40CFR 60 EPA PS1
Measuring locationIn-situ, non-contact
Self-check, protective functionsAutomatic zero- and span check
Automatic soiling correction
LED light sourc: no readjustment needed
Automatic measuring range selection
Automatic fail safe shutter in case of purge air failure (option)
Temperature compensation (option)
System componentsD-R 290 M measuring head
D-R 290 R reflector
D-R 290 A operating and display unit
D-BL purge air unit
D-R 290 E mounting flange with tube
D-SK fail safe shutter (option)
Physical measuring value0…1.6 Extinction
0…97.5% Opacity
Derived measuring values Transmission, opacity, extinction, dust concentration in mg/m3, mg/m3, mg/standard m3 (after calibration QAL2)
Measuring range transmission100…0%
Output range transmission Freely programmable
Measuring range opacity0…100%
Output range opacityFreely programmable
Measuring range extinction0…1.6 EXT
Output range extinctionFreely programmable
Measuring range dust concentration 0…10000 mg/m3 (depending on calibration)
Output range dust concentrationFreely programmable
Lowest detection limit0.75% for measuring area 0...0.1 extinction
Combined standard uncertainty acc. to QAL1, DIN EN 14181 1.8%, related to the certified measuring end value 15mg/m3
Light source, spectral range450…680 nm, SWBD LED white
Process connectionConnection flange, bolt circle 100 mm, tube ID = 59 / 83 / 105 mm
Power supply Sensor supply voltage +5 VDC or ±15 VDC
Ambient temperature (operational) -20…+50 °C (-4…122 °F), optional higher
IP protection class (IEC 60529)IP65
EX zoneOption: Ex II 3G Ex pz II T4, Ex II 3D Ex pz II T4
Dimensions (HxWxD)370 x 190 x 400 mm
Weight10 kg
MaterialAluminum, painted blue RAL 5017
Process connection Connection flange, bolt circle 100 mm, tube ID = 59 / 83 / 105 mm
Ambient temperature (operational) -20…+50 °C (-4…122 °F), optional higher
IP protection class (IEC 60529)IP65
EX zoneOption: Ex II 3G Ex pz II T4, Ex II 3D Ex pz II T4
Dimensions (HxWxD)370 x 190 x 270 mm
Weight7 kg
MaterialAluminum, painted blue RAL 5017
Digital interfacesRS 485 - Modbus RTU (option), Profibus DP (option)
Analog outputs2 x 4…20 mA, 500 Ohm, 4 mA Zero, 0 mA Error, programmable assignment of two output ranges to two analogue outputs
Analog inputs 1 x 4…20 mA, programmable
Digital outputs6 x Relais, programmable, max. 48 V, 0.5 A
Digital inputs 6 x potential free, programmable
Power supply90...264 VAC, 48...62 Hz, 30 VA
Display, status LEDsMeasuring values can be displayed on D-R 290 AW2/AZ2 optionally as opacity, extinction or scaled as dust concentration in mg/m³
Ambient temperature (operational)-20…+50 °C (-4…122 °F), optional higher
IP protection class (IEC 60529)IP65 (with D-R 290 AG2)
Dimensions (HxWxD) 260 x 190 x 220 mm
MaterialAluminum, painted blue RAL 5017
Power supply115 / 230 VAC, 50 / 60 Hz, others on request
Power consumption0.37 kW (50 Hz) / 0.43 kW (60 Hz)
Air supply capacity40 m3/h (50 hPa) / 60 m3/h (25 hPa), others on request
Ambient temperature (operational)-20…+50 °C (-4…122 °F), optional higher
IP protection class (IEC 60529)IP55
Dimensions (HxWxD)480 x 450 x 320 mm
Weight12 kg
MaterialStainless steel 1.4301
  • The suitability of the D-R 290 for the listed ranges depends on the kind of dust, the size distribution and the duct diameter.
  • Subject to technical modifications.

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