AccuWeb EVO 150, Instruction Manual

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AccuBeam 3 Digital Line Guide Sensor 68
Example # 2 - Tracking an edge:
1) Suppose you have a narrow black line and a wide yellow stripe printed on silver metalized
film, as shown below:
2) Now, let’s assume you want to track the left edge of the yellow stripe. Since there will
probably be several edges in the sensor’s field of view you will need to indicate which edge
you want the sensor to track.
a) Position the sensor so that it is approximately centered over the left edge of the yellow
stripe.
b) Select the Calibration parameter and press ENTER to start the auto-calibration
procedure.
c) When the “Select line/edge” message appears, adjust the position and width of the
selection window so that it straddles the left edge of the yellow stripe and covers roughly
equal amounts of the stripe and metalized area to its left. Make sure the window
does not
touch the right edge of the stripe. Use the DOWN key to adjust position and the UP key
to adjust size.
Note: It may not be necessary to adjust the selection window if there is only one edge in
the sensor’s field of view and the sensor has been centered over it.
d) As you adjust the window size and position, the sensor will continuously analyze your
selection and pick the best parameter settings to track the edge you selected. If it can
reliably track this edge it will place an indicator dot directly under it.
e) If the indicator dot is not visible or is in the wrong place, adjust the selection window size
and position until the indicator appears under the desired edge.
Tip: To exit from the auto-calibration procedure without changing any settings, press the
UP key repeatedly until the “Exit?” message appears, then press ENTER.
3) When the indicator dot is under the edge you want to track, press the ENTER key to
complete the auto-calibration. The sensor will then store the new parameter values in the
current Job Profile’s memory. For the material used in this example the parameters will be set
to the following values:
Right edge of web
Scan direction (Left-to-Right)
Selection window
Left edge of web
Registration edge
Sensor’s field of view
(0.625” [15.9mm] wide)
Yellow stripe