Photoelectric sensors

Your Benefits

  • Precise laser light spot for highly accurate switching behavior
  • High optical ambient light immunity reduces incorrect switching and thus machine downtime, even when modern energy-saving lamps are used
  • The highest degree of machine design flexibility BGS (background suppression) eliminates the effect of undesired background reflections. In addition, autocollimation allows detection through small drilled holes
  • One device for detecting both transparent objects and the smallest non-transparent objects, thus reducing the variety of sensors and saving on storage costs
  • IO-Link facilitates initial system performance diagnostics and uses additional sensor functions (optional) to reduce complex control programming


Maximum performance for handling demanding detection tasks involving tiny objects. With its precise laser light spot, the W4SL-3 miniature product family sets new standards by providing high optical light immunity from undesired background reflections and immunity to ambient light - even from modern energy-saving lamps. The combination of SICK's proprietary laser and ASIC technologies reduces incorrect switching to minimize machine downtime, reducing the variety of devices and saving on storage costs. The photoelectric sensors also provide an IO-Link interface for initial system performance diagnostics. Furthermore, IO-Link permits the integration of additional functions such as meters directly into the sensor. There is no need for complex control programming.

At a glance
  • Precise laser light spot, laser class 1
  • Teach-in pushbutton can be switched between detection of transparent and non-transparent objects
  • Sensing ranges between 25 mm and 60 m
  • Latest SICK proprietary ASIC and laser technologies with second emitter LED to provide outstanding background suppression and ambient light immunity
  • Choice of adjustment via teach-in button, potentiometer, cable, or IO-Link


Technical overview

  • Technical data overview

    Technical data overview

    Dimensions (W x H x D)12.2 mm x 41.8 mm x 17.3 mm
    Sensing range max.

    25 mm ... 300 mm 1)

    0 m ... 12 m 2)

    0 m ... 60 m

    Light sourceLaser
    Type of lightVisible red light
    Enclosure rating



    Housing materialPlastic Novodur

    Potentiometer, 5 turns


    Single teach-in button

    Cable 3)


    • 1) Object with 90 % reflectance (referred to standard white, DIN 5033).
    • 2) Reflector PL80A.
    • 3) Adjustment via cable (ET): white cable or PIN2 according to the desired sensitivity > 2 ... < 8 s or put > 8 s on L+ (PNP) or on M (NPN).
All technical data can be found accompanying the individual product