As contactless measurement devices, photoelectric Distance sensors are suitable for numerous areas of application. Different operating principles are available, depending on the distance to be measured. DTR-C23 and DTL-C23 sensors use a triangulation method for highly accurate distance measurement at short range. For longer ranges, the optical time-of-flight (TOF) method is used by DTL-C55 sensors. With both methods, distance measurement is largely independent of target color or surface characteristics and repeatability is high. Detected distances can be output via an adjustable analog output and, for a digital output, a switching window of acceptance may be configured by teach-in.
The housings of DTR-C23 and DTL-C23 sensors (20 x 34 x 12 mm) and DTL-C55 sensors (50 x 50 x 23 mm) are extremely water-resistant with an IP67/IP69K enclosure rating. DTL-C55 sensors also have Ecolab certification, being highly resistant to industrial cleaning agents and therefore ideal for hygienic areas.
Precise short-range measurement
DTR-C23 and DTL-C23 Distance sensors operate according to the principle of triangulation using either red light or laser. Types with red light measure distances of 20 to 80 mm or 30 to 200 mm, while the measurement range for laser types is 20 to 100 mm. Repeatability is excellent with values between <1 mm and <0.25 mm. A typical application is measurement of the thickness of material on winding rolls. By setting the range of the 1 to 10 V analog output to the start and end thicknesses, optimum resolution can easily be obtained. This compact sensor is also suitable for small-part detection and checking of position, height or thickness.
Longer distances measured and transmitted directly in digital form
The DTL-C55 Distance sensor uses the optical TOF method to measure distances up to 5000 mm. In the IO-Link version, measurements are passed directly to the control system as millimeter values in digital form, with no need for an additional analog-to-digital converter and no signal drop for long lines. The IO-Link Smart Sensor Profile simplifies handling and minimizes integration cost. This profile also supports initial setup of sensors with user-friendly standard parameters and teach functions. Existing control system parameters are transferred to each newly installed sensor via the bus. In addition, IO-Link provides comprehensive diagnostic options and additional information such as operating hours, signal quality or the number of switching operations. With two virtual switching points settable either via teach-in or direct parameter write-in, the sensor is particularly suitable for use in mobile logistics. For example, on forklift trucks its long measurement range will reliably detect goods already on shelves and measure any free space for more items, ensuring full utilization of storage.
Distance measurement is also possible by utilizing the analog voltage outputs available on other cubic models.