Visibility Monitors

Flow Monitors


D-R 220T Visibility monitor

Visibility Monitor for road tunnels using optical transmission principle. Sensor for ventilation control system or fire alarm system. Reliable measurement parallel to the tunnel axis.

  • measurement parallel to tunnel axis, continuous measurement
  • measurement along a distance of 10m, no spot measurement
  • corrosion resistant against tunnel atmosphere
  • determination and correction of the pollution of optical surfaces
  • measuring head and reflector can be exchanged quickly N
    - no tools required
    - no re-alignment required
  • signal transfer
    - per analog signal and relay outputs
    - per RS485 Modbus RTU
  • hermetically sealed housing - no gas diffusion to optics or electronics
  • dust protection tube prevents contamination of the optics
  • long maintenance intervals
  • quick and easy startup with or without PC
  • Applications
  • Technical Data
  • Downloads

    suitable to measure visibility

  • in road tunnels
  • in factories

    suitable for early fire detection

  • in road tunnels

    suitable to measure dust concentration

  • in factories
D-R 220T Application data
sample gas
0 - 95 % rel. humidity (not condensing)
measurements extinction coefficient K in km-1 opacity as an option
extinction coefficient K [km-1] (typically) 0 - 15 km-1
measuring path distance measuring head - reflector: 9.5-11m,
path length 19-22m
orientation parallel to tunnel axis,
ambient temperature -20 to +50 °C, dT/t < 10°C/h
D-R 220T technical data
measuring principle measuring the optical transmission of visible light which passed a measuring path twice
status output 2 x relay NO, programmable, max load 48V, 0,5A
service interface USB 1.1
service software D-ESI 100*
power supply 24 VDC, +- 10%, 0,4A
protection IP 65
dimensions (h x w x d) ca. 150 x 220 x 140 mm
weight ca. 2,7 kg
material polyamide, ca. RAL5017
fire class: B1 (UL 94 V0)
D-R 220T dust protection tube
dimensions (h x w x d) ca. 280 x 110 x 110 mm
weight ca. 3 kg
material 1.4571
D-RV 290 BW bracket
dimensions (h x w x d) 160 x 280 x 190 mm
weight 4 kg
material 1.4571
fixation 4x bolt d= 8 to 10mm
D-TB 100T A terminal box
power supply 90 - 264 VAC, 48 - 62 Hz, 30 VA
includes 24VDC supply for D-R 220T M
dimensions (h x w x d) ca. 160 x 160 x 110 mm
ambient temperature -25 to 55°C
protection IP 66
weight ca. 1,5 kg
material polycarbonate, ca. RAL 7035 fire class: B1 (UL 94 V0)
fixation 4 x bolt od= 8 to 10 mm
remarks * variants
Subject to technical modifications!