LINK Systems OmniLink II Press Automation Control - Manual (Page 71)

August 30, 2002 Manual Version 1.0 4.22
6. Calculated Degrees Before Top Dead Center. For variable speed presses, the OmniLink II Press
Automation Control uses a nonlinear equation whose coefficients are based on the settings made
in items 1-4 for highest and lowest speed. This equation calculates the correct angle before TDC to
apply a stop signal to stop the press at the top of the stroke based on the measured stroking speed,
shown as the Speed At Stop Initiation in item 5. This angle appears on the screen each time the
press stops as the number indicated as Calculated Degrees Before Top Dead Center, and will vary
with actual stroking speed. This calculated number aids in refining settings in items 2 and 4 to stop
near top as you perform the automatic top stop calibration for variable speed presses. You cannot
enter a setting for this item.
7. Co A and Co B. These are the coefficients of the nonlinear equation that compensates the top stop
signal for variable speed presses for different speeds. These numbers are based on the settings you
make in items 1-4. They have no utility other than possibly being useful for troubleshooting with
Link personnel over the phone. For fixed speed presses, these coefficients will both be 0 since both
Low Speed SPM and High Speed SPM will be entered as the nominal speed of the press, and Low
Speed and High Speed Degrees Before Top Dead Center will be set the same. You cannot enter
settings for these coefficients.
Section 4.2.3.1 Top Stop Calibration for Fixed Speed Presses
To set up the stop initiation angle for fixed speed presses:
1. Go to the Speed Adjusted Top Stop Compensation screen. Turn the Run/Program Switch to
Program. Enter settings for both the Low Speed SPM and the High Speed SPM that are equal to the
nominal press strokes/min. If the press legend plate indicates that the press strokes at a fixed 60
strokes/min, this is the value that should be entered. Enter settings of 0
0 for both the Low Speed
Degrees Before Top Dead Center and High Speed Degrees Before Top Dead Center.
2. Turn the Run/Program switch to Run, select the Continuous mode of operation on the press control
and initiate Continuous Stroking. After a few strokes, press the TOP STOP softkey on the Speed
Adjusted Top Stop screen (do not top stop the press using any top stop button that may be provided
with the press control). Since both Low Speed and High Speed Degrees Before Top Dead Center
were set to 0 in step 1, the OmniLink operator terminal will initiate a stop signal at Top Dead Center
(0
0 ), and the press will travel into the downstroke before stopping. Look at the operator terminal
angle display in the upper left corner of the display to read the angle at which the press slide comes
to a stop. Since the stop angles (Low and High Speed Degrees before Top Dead Center) entered in
step 1 were both 0, the reading on the angle display is the number of degrees the press took to stop.
3. Turn the Run/Program switch back to Program. Enter the number on the Operator Terminal angle
display into both the Low Speed and High Speed Degrees Before Top Dead Center as an
approximate setting
4. Return the Run/Program switch back to Run and initiate Continuous stroking again. Press the Top
Stop softkey on the Speed Adjusted Top Stop screen and read the operator terminal angle display
to observe where the press stopped. Since the stopping time and distance (angle) for the press may
be different depending on the angular region over which the press stops, the settings in step 5 may
not stop the press as close to the top as desired. To refine the adjustment, turn the Run/Program key