Page 21 - Industrial_Technology_EXTRA_1st_June_2020_Classical
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A photoelectric contrast sensor from the   Set-up is accomplished either using a three-
       Contrinex Cubic Small range is ideal for this   button keypad on the sensor, or via IO-Link, a
       application. This versatile device incorporates a   standardized point-to-point serial connection
       single-lens autocollimator, delivering a narrow   protocol. Photoelectric contrast sensors are
       optical beam that allows detection of very small   available with industry-standard push-pull 4-wire
       features. The choice of red, green or blue LED light,   output. Connection to the customer’s control system
       auto-selectable during set-up, ensures optimal   is via a PVC-sheathed cable with the choice of an
       contrast resolution.                 integral M12 connector or a hermetically sealed
         Immediately after the applicator, a single sensor   entry.
       is mounted beside the conveyor; adjustable   www.plusautomation.co.uk
       mounting brackets makes for easy positioning. As
       the label on each carton passes the detection point,
       changes in contrast trigger the sensor. The transition
       from carton surface to label body identifies the
       position and alignment of the label itself, while the
       well-defined contrast between printed content and
       the label body ensures reliable detection of even the
       smallest print marks.
         If the label is wrongly aligned or the print
       markings missing, the sensor triggers a reject
       mechanism that diverts the carton to a holding area
       for investigation. An operating range up to 12mm
       allows adequate clearance between sensor and
       target, while the compact 40mm x 50mm x 15mm
       PBTB plastic housing is both mechanically robust
       and small enough to accommodate any space
       constraints.

         June 2020 • INDUSTRIAL TECHNOLOGY EXTRA! • p21
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