The TunnelCraft III CO/VIS Air Quality Monitor (AQM) uses infrared light and visible light to measure carbon monoxide and visibility in a single compact instrument.

The AQM consists of a transceiver that projects infrared beams to a reflector unit mounted 3m away. The reflected light is received by the transceiver and the specific absorption is measured to determine the visibility dimming coefficient and carbon monoxide concentration in the tunnel atmosphere.

Key Featurestc3_800px

  • Measurement of CO by infrared absorption
  • High resolution measurement of visibility
  • Accuracy +/-1ppm for CO, 0.0002m-1 for visibility
  • Designed to withstand the harshest environments
  • RS232 or RS485 – Modbus output optional
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Gas Species Options Single or multi-gas measurements available: CO & Visibility
Measuring units ppm for CO, m- or m for visibility
Response Time CO 2mins / Vis 10s – 2min Selectable
Ambient Temperature -20°C to +50°C
Power supply 12V DC @1.5A
Construction Corrosion resistant epoxy coated aluminium housing sealed to IP66
Analogue outputs 3 x 4-20mA current outputs as standard, isolated, 500Ω load max, fully configurable
through TunnelCraft software.
Relay Outputs 3 x volt-free SPCO contacts, 50V, 1A max, configurable as alarm contacts
Serial Data RS485 Modbus Protocol

To view theTunnelCraft 3 full specification please click here to download the product datasheet.

Lang Filetype Document Link Size
English Adobe_Acrobat_Pro_PDF Tunnel Craft 3 Datasheet Download File 400kb
English Adobe_Acrobat_Pro_PDF GCEM 40 Series Manual Download File 400kb

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