Rockwell Automation 42CRC Color Registration Control - Manual (Page 7)

5
42CRC Color Registration Control
After the control has been installed and aligned, it must be set for the
particular operation. An important feature of the control is that it gives the
user complete flexibility to select any combination of the four major
operating modes listed below via a convenient external function selector
switch. See Figures 5, 6, and 7.
a. Latch Operation
This function allows the user to latch the switched output “ON” for an in-
definite period when a mark is detected. The output is reset by applying a
positive 4 to 30 VDC to the “white” GATE/RESET input lead or by simply
switching this lead to the B+ supply. Electromechanical or solid state con-
tacts can be used to reset the control. This function enables the output dura-
tion to be extended, and the output reset later in the machine cycle. The
“Latch” switch positions are “A” through “D”.
b. Non-Latch
In the non-latch mode, detection of a mark turns the switched output “ON”
for an adjustable dwell time of up to 250 milliseconds. After the dwell
time, the output will automatically reset. This mode is similar to an adjust-
able one-shot. Non-latch positions are “E through H”.
c. Light and Dark Mark Sensing
The 42CRC can be set to energize on the leading edge of light marks on a
dark background or the leading edge of dark marks on a light background.
The alphabetic positions on the function switch have letters with white
backgrounds and letters with black backgrounds. Select white background
positions for light mark sensing and black background positions for dark
mark sensing.
d. Automatic Operation
“Automatic” mode provides stable, adjustment-free sensing for most ap-
plications. The 42CRC automatically adjusts the sensitivity, compensating
for variations in background colors and lens contamination. It also provides
additional gain for the low contrast marks on dark backgrounds and scan-
ning of glossy surfaces at an angle.
In this position the orange LED marked “AUTO” is “ON” and the manual
sensitivity adjustment is NOT functional. Switch positions for this mode
are A, A , C, C , E, E , G, G .
e. Manual Operation
This operating mode extends the control’s sensing capability for very low
contrast marks (e.g., pastel colors) on light backgrounds. Signal processing
in the 42CRC continually corrects for variations in background signal
level. The result is a mark detection system that has a more stable threshold
Operating Modes