D-R 820 F

Extractive scattered light analyser


Extractive dust monitor for wet sample gas to monitor low to medium dust concentrations.


  • extractive measurement, continuous measurement, dilution of the sample
  • suitable for systems with variable gas speed
  • hyperkinetic sampling
  • allows calibration to measure the dust concentration in mg/m3
  • single sided mounting to the chimney
  • automatic zero and reference point check
  • automatic measurement and correction of contamination of optical surfaces
  • laser light source with long lifetime
  • easy installation, adjustment and maintenance without a PC
  • local control panel and LCD display


Suitable for dust concentration measurement

  • at garbage, hazardous waste and sewage sludge incinerators
  • at power stations with gas, oil, coal or co-firing
  • at systems behind the flue gas scrubber
  • at systems behind desulfurization
  • at systems with low exhaust temperature and constant or occasional dew point

Technical Data

  • D-R 820F Application data

    Flue gas type Air, flue gas, non flammable process gas
    Flue gas temperature Above due point,
    ≤ 200 °C standard,
    up to 500 °C option
    Inner stack/duct pressure (relative to ambient pressure) -50 … +10 hPa standard,
    -50 … +50 hPa option
    Flue gas relative humidity 0 … 95 % RH, non-condensing
    Stack/duct inner diameter 0.4 … 10 m
  • D-R 820F Technical data

    Measuring principle extraction of sample gas, dilution and heating to vaporize H2O aerosols. Consequent measurement of light intensity being scattered in forward direction by dust particles
    light source laser diode, red 650 nm
    type in situ, mounted at stack, probe in contact with sample gas
    system components D-R 820F P probe incl. extractive system
    D-R 820F blower unit
    D-R 820F SU Supply, control and display unit
    measuring range can be parametrized
    expanded uncertanty acc. to EN 14181 / EN ISO 14956 / EN 15267-3 better than 1,5 mg/m3 at particle size 1-2mü
    output range scaling of scattered light values in mg/m3, assigned to analog output, range switching to 2nd range as option (ratio 1:3), display of measured values in mg/m3
    process connection flange similar to DN80, PN6, pitch circle 150mm, tube ID = 100mm
  • D-R 820F P probe with extractive system

    power supply 200-264 VAC, 1.500 VA, 24 VDC, from D-R 820F SU,
    others on request
    protection IP 55
    dimensions (h x w x d) 1.050 x 600 x 1.500 mm (1.000 mm immersion depth)
    material housing: FRPl
    probe: 1.4517, hastelloy 2.4610*
    weight ca. 45 kg
  • D-R 820F SU supply and display unit

    output signal 4 – 20 mA / 500 Ohm
    status output 4 x relay, max. load 35V 0,4A
    status input 1 x dry contact, purge
    power supply 230 / 400 V, 50Hz 3L, N, PE, 3 x 16A, 3.500 VA
    supplies D-R 820F P and D-R 820F Blower, others on request
    protection IP 55
    dimensions (h x w x d) 400 x 600 (1.200***) x 410 mm
    *** width if cabinet is open
    material sheet steel, painted RAL 7035
    weight ca. 20 kg
  • D-R 820F Blower unit

    power supply 2 x 230/400 V 50 Hz, 3L, PE, from D-R 820F SU
    others on request
    protection IP 65
    dimensions (h x w x d) 600 x 800 x 400 mm
    weight ca. 40 kg
    Bemerkung * variants
    ** the suitability of the D-R 820F for the listed ranges depends on the kind of dust and the size distribution
    Subject to technical modifications!