Tunnel visibility sensor
The TunnelCraft 3 CO/NO/VIS Air Quality Monitor (AQM) uses both infrared light and visible light channels to measure carbon monoxide, nitric oxide 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, carbon monoxide and nitric oxide concentration in the tunnel atmosphere.
› Measurement of CO & NO by infrared absorption
› Maintenance limited to annual cleaning of optical surfaces
› High resolution measurement of visibility
› Current and relay outputs direct from sensor
› Accuracy +/-1ppm for CO, +/-2ppm for NO, 0.0002m-1 for Vis
› RS232 or RS485 - Modbus output optional
› Designed to withstand the harshest tunnel environments
› Also available as a single channel instrument