Page 21 - Industrial_Technology_EXTRA_1st_June_2020_Classical

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