LINK Systems OmniLink II Press Automation Control - Manual (Page 62)

August 30, 2002 Manual Version 1.0 4.13
be accommodated so that adjustment on a frequent basis is not necessary. A typical wear margin of
20% is usually sufficient. To determine the number to enter for the Clutch Engagement Time Limit with
a 20% wear margin, take the longest time recorded and multiply it by 1.2. For example., if the longest
time recorded is 100 milliseconds, enter a value of 120 milliseconds for the Clutch Engagement Time
Limit.
Section 4.2.1.8 Setting Brake Monitor Top Stop and Brake Monitor Mid Stroke Stop Limits
The Brake Monitor Top Stop Limit and the Brake Monitor Mid Stroke Limits are set on the Machine
Parameters menu. However, during your initial system configuration only, before performing the
steps listed in this section of the manual to determine the settings for Brake Monitor limits:
1. If you have a variable speed press and are planning to adjust stroking speed through use of the
OmniLink II LCD Operator Terminal and the Analog Input/Output Board, you should first
access the Speed Configuration menu by pressing the SPEED CONFIG softkey on the
Machine Params menu and perform the steps described in Section 4.2.2 of this manual. If not,
proceed directly to step 2.
2. You should then return to the Main Configuration menu. Push the Top Stop Calibration
softkey to go to the Top Stop Calibration menu and perform the Top Stop Calibration for the
press as described in section 4.2.3 of this manual.
Once you have finished the Top Stop Calibration, return to the Machine Parameters menu and
determine the proper Brake Monitor Top Stop and Mid Stroke Stop Limits as described in the
following paragraphs of this section of the manual.
To determine Brake Monitor Top Stop Limit and Brake Monitor Mid Stroke Limit settings:
1. It advisable to determine stopping time of the press with the heaviest upper die that you use in the
press and, if the press is a variable speed press, to run at the highest stroking speed for which the die
is run in the press. Adjust the press shutheight so that the upper and lower dies don’t close. If the
press has a slide counterbalance, it should be set for the weight of the upper die. The stopping time
of the press will increase with upper die weight and stroking speed, and will vary with
counterbalance pressure. It is also recommended to make adjustments (when adjustment is
provided) to set clutch and brake clearance to the minimum value specified by the press
manufacturer. This should reduce stopping time.
The worst case stopping time is what you are trying to determine, so that it is not necessary for you
to have to repeatedly change the brake monitor stop limit settings as different dies are used in the
press. Of course, you may add production jobs at a later time where die weight or stroking speed
produces stop times that exceed the initial worst case values, requiring limits to be increased.
2. Turn the Run/Program switch to Run and start the press stroking in Continuous Mode. After the
press has made two or three strokes, press the Top Stop softkey on the Machine Parameter menu
screen. The OmniLink II Press Automation Control will top stop the press and a stopping time will
be displayed in milliseconds (thousandths of a second) for Brake Monitor Actual Stop Time. To the
right of the stop time (TOP) should appear, indicating that this is a top stop time measurement.
Record this top stop time and repeat this step, recording top stop time each time you stop.