Led light source selection, Additional features – Rockwell Automation 42CRC Color Registration Control User Manual
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9
42CRC Color Registration Control
d. Contrast Check
Test Points are provided on the back cover of the control (see Figure 5,
Page 6) to determine if sufficient contrast exists between the mark and the
background for reliable operation. The test point contacts are made of nick-
el plated stainless steel and can be immersed in water or short circuited
without affecting the operation of the control.
To check contrast, set the control in the manual mode. Set the web station-
ary with the light spot of the control on the background. Using a DC volt-
meter (100K ohm/volt), connect the test probes to the test points. Note the
reading and repeat the measurement with the light spot centered on the
mark. If the difference between the two readings is in excess of 300 mV,
there is sufficient contrast for reliable operation.
Check the mark/background with both the green and red LEDs. Use the
LED that provides the maximum voltage difference. By making this con-
trast check, you can also determine the correct mounting angle (Figures 2,
3, and 4) by adjusting the scanning angle to obtain the maximum voltage
difference.
Led Light Source
Selection
BACK-
GROUND
COLOR
REGISTRATION MARK COLOR
WHITE
BLUE
GREEN
YELLOW
ORANGE
RED
BLACK
WHITE
RED
OR
GREEN
RED
RED
OR
GREEN
GREEN
GREEN
RED
OR
GREEN
BLUE
RED
OR
GREEN
RED
OR
GREEN
RED
OR
GREEN
RED
OR
GREEN
RED
RED
OR
GREEN
GREEN
RED
RED
OR
GREEN
RED
OR
GREEN
RED
OR
GREEN
RED
GREEN
YELLOW
RED
OR
GREEN
RED
OR
GREEN
RED
OR
GREEN
RED
OR
GREEN
GREEN
GREEN
ORANGE
GREEN
RED
OR
GREEN
RED
OR
GREEN
RED
OR
GREEN
GREEN
RED
RED
GREEN
RED
RED
GREEN
GREEN
RED
BLACK
RED
OR
GREEN
RED
OR
GREEN
GREEN
GREEN
RED
RED
FIGURE 8
Additional Features
(Continued)