Stack/Duct Probe

WHAT IT DOES

  • The probe is an engineered solution for our series of GasFinder analyzers to remotely monitor the path average concentration inside of a stack or duct

 HOW IT WORKS

  • The analyzer can be mounted locally or remotely
  • Fibre optic cable carries the laser light from the analyzer to the remotely mounted stack/duct probe (transceiver)
  • The active measurement path is formed by the laser passing through the stack/duct and being returned by the retroreflector on the opposing flange.
  • The laser light is then collected and the signal is carried back to the analyzer via coaxial cable
  • The ppm-m concentration is then transferred from the analyzer to the PLC or DCS

SCHEMATIC

AIR PURGE

  • In some cases, condensation and accumulated dust can cause optical interference or a blocked path.
  • For cases of positive pressure, instrument air can be tubed in to the spacer flange to provide a flow rate of 1-5 l/min to keep the dust from settling
  • In instances of negative pressure, the ¼” NPT port in the spacer flange can be left open to allow air circulation

OPTICAL ALIGNMENT

  • Install the transceiver and leave the retro flange off
  • Remove cover plate on the transceiver
  • Connect the visible laser from the troubleshooting and diagnostic kit (most stacks and ducts have a particulate load and the beam should easily be seen)
  • Adjust the alignment screws so the visible laser beam is aimed through the opposing flange port
  • Install the retro flange, remove the visible laser, and replace the cover plate on the transceiver

 

 CONSIDERATIONS

  • It is important that the flanges are welded orthogonally to the duct and that the two flanges are mounted at the same height
  • For high concentration applications
    • Configure the probe to be “pitch-catch” (transmitter and receiver) to only allow a single pass for the laser
    • Insert a plenum to limit the active measurement path
  • For stack temperatures over 120ºC (250ºF), it is recommended to install a spacer flange

 

SPECIFICATIONS

OPERATIONAL SPECIFICATIONS

  • Measurement Principle: TDLAS
  • Open-Path Length: 0.3 – 20m (1 – 65 ft)
  • Gas Temperature: -40ºC – 150ºC (-40ºF – 302ºF)
  • Gas Pressure: Max 300 mbar
  • Ambient Temperature: -45ºC – 80ºC (-49ºF – 176ºF)
  • Ambient Humidity: Operating; non-condensing 5-95% RH
  • Dust Concentration: Max 2 g/m3

SIGNAL CONNECTOR SPECS

  • Optical Connector: FC/APC Female (Signal-In)
  • Coaxial Connector: BNC Female (Signal-Out)
  • Power Supply: None Needed
  • Opening for Gland: 20mm

PHYSICAL SPECS

  • Dimensions: 160 x 160 x 300mm (6.3 x 6.3 x 11.8 in)
  • Weight: 4.5 kg (9.9 lbs)
  • Protection: IP66/NEMA 4x
  • Materials: AISI316
  • Housing: AISI316 with PE or PTFE
  • Window: Borosilicate, fused silica, or sapphire
  • Gaskets: NBR, Viton, or PTFE
  • Flange Size: 3” ANSI 150#

GAS SPECS

COMPATIBLE ANALYZERS

  • GasFinder2-MC

    The GasFinder2-MC is a rack mounted multi-channel fibre coupled instrument that can be used to monitor up-to 8 different Stack/Duct Probes at the same time.

    Click here to go to the GasFinder2-MC product page for more information.

  • GasFinder-FCr

    The GasFinder2-FCr is a rack mounted single-channel fibre coupled instrument that can be used with the Stack/Duct Probe.

    Click here to go to the GasFinder2-FCr product page for more information.

  • GasFinder2-FC

    The GasFinder2-FC is a portable single-channel fibre coupled instrument that can be used with the Stack/Duct Probe.

    Click here to go to the GasFinder2-FC product page for more information.