SITRANS proxy SMP 8500/R. Robust reflective light sensor with rail approval

Telco's SM 8500/R IR light barrier system uses the latest technology including high-level interference immunity complying to IEC standards. Pulsed infra red light from an emitter diode is diffusively reflected from an object in the detection area and picked up by a receiver unit in the same housing. A transistor output activates when the received signal is of sufficient strength.

The scanning range is dependent on the size, colour and surface properties of the object. The beam width guarantees reflection even from highly uneven surfaces or from materials with high roughness depths. The scanning range is adjustable via a potentiometer. A selector is also available for light/dark functions. The electronics are fully sealed within the housing to provide shock and vibration resistance and the high IP67 protection class. The unit is therefore suitable for use in areas requiring robust equipment.

Benefits of the SMP 8500/R reflective light sensor

  • Extremely resistant to dirt
  • 0–0.5 m scanning range
  • Direct 10 - 30 VDC connection
  • Light/dark switching
  • Transistor output
  • LED function display
  • Protection class IP67

Certified according to:

  • DIN EN 50102:1997-09 (external mechanical loads – IK08)
  • EN 50121-3-2:2015 (electromagnetic compatibility)
  • EN 50155:2007 + Corr. 2010 (electronic equipment in rail vehicles)
  • EN 55011:2009 + A1:2010 (interference suppression in industrial applications)
  • EN 61000-4 (immunity of electrical/electronic equipment)


Sitron Sensor GmbH
Nickelstr. 4
30916 Isernhagen

Phone: +49 511 728 50-0
Fax: +49 511 728 50-33
E-Mail: office(at)

On-site point of contact

You can find your personal Sitron customer consultant here.