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TunnelTech 700

Electrochemical CO, NO & NO2 Air Quality Monitor

The TunnelTech 700 is an advanced technology analyser which gives complete flexibility in the choice of measurement options.


The TunnelTech 700 Air Quality Monitor, is an essential part of any road or rail tunnel safety system. Firstly, it monitors the atmosphere within the tunnel and ensures that the tunnel
ventilation system provides sufficient clean air to protect tunnel users health and for drivers to clearly see the road ahead.


The TunnelTech 701 analyser electrochemical cell technology to determine CO, NO & NO2 concentrations and optical attenuation to monitor Visibility levels.


As there are no moving parts, reliability levels are very high and maintenance requirements are low. The sight tubes have been designed to ensure that airborne dust and contaminants do not reach the optical windows and cause drift

Features & Benefits

Related Products

TunnelTech 305 - Air Flow Monitor
TunnelTech 201 - Luminance Monitor

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      TunnelTech 700 Specification

      Gas SpeciesSingle or multi-gas measurements available: CO, NO2, NO & Vis
      Measuring Unitsppm for CO & NO, PPb for NO2, m-1 or m for visibility,
      CalibrationAutomatic zero calibration – manual span check
      Measurement TechniqueElectrochemical Cell, LED Transmitivity for Visibility
      Measurement range (typical) CO : 0 – 300ppm , NO : 0 – 30ppm , NO2 : 0 – 5/10ppm, Vis: 0 – 0.015 m-1
      ConstructionCorrosion resistant epoxy coated aluminum housing sealed to IP66
      Serial DataBi-directional RS485 Modbus Protocol
      Display32 Character alpha-numeric back-lit LCD
      Power Supply24V DC, 30 VA from separate power supply

      For a full product specification please download the product brochure below.