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The DSL-320 Opacity Monitor uses a double pass light transmission technique to measure dust, smoke and particulate emissions present in an exhaust gas flow in a duct, stack or flue. A light beam, emitted from the Transceiver, (TRX), passes across the duct, stack or flue to a Reflector, which returns the light beam to the TRX. Any dust or smoke particles present will attenuate the light beam and cause the intensity of the light received by the TRX to fall. The amount of light lost in crossing the duct, stack or flue is the Opacity and this correlates to the amount of dust or smoke present in the gas flow.

  • In-situ measurement directly in exhaust gas flow
  • Measurement reading as % Opacity
  • In-situ zero and calibration check facility
  • Choice of interface options enabling easy integration into plant control system
  • Free utility software for PC based setup, control and data logging
  • Optional Operator Interface with different mounting configurations

IP65 rated external enclosure

  • Measuring Principle : Light Transmission
  • Operating Wavelength: 510 – 540 nm (green LED)
  • Measurement Reading: Opacity (%)
  • Measuring Range: 0 – 100 % Opacity (user selectable)
  • Accuracy : + / – 2 %
  • Voltage : +24 VDC (optional 90-260 VAC PSU available)
  • Analogue Outputs: 4.0 – 20.0 mA
  • Ambient Operating Temperature: -20 to + 50 °C

Ingress Protection – TX/RX Heads : IP65 for external use

  • Simpler installation than single pass opacity monitors
  • Better accuracy over shorter path lengths, i.e. smaller duct diameter
  • Rugged design with no moving parts so low maintenance
  • Latched head design to enable ease of access to optics for maintenance
  • Non compliant processes
  • Boilers and furnaces
  • Crematoria
  • Incinerators
  • Post particulate removal systems such as filter bag houses, electrostatic precipitators or cyclones
  • Marine industry for monitoring smoke emissions from diesel engines, incinerators and boilers

DSL-320 Brochure