LINK Systems OmniLink 5000 - Manual (Page 19)

April 17, 2000 Man ual Revisio n 1.0
3.4
Figure 3.5: Example Data Window.
Section 3.2 Data Windows
Peak tonnage monitors capture the maximum tonnage seen by each strain gauge over the stroke. This
maximum tonnage is used for comparison to setpoints in determining if an alarm should be generated to
stop the production process. While this is adequate for most applications, complex tooling can produce
multiple peaks resulting in only the highest peak being checked against setpoints. Where closer
monitoring is desired in these applications, the tonnage monitor module provides up to four “Data
Windows” to monitor additional peaks other than the absolute maximum peak tonnage. These
additional peaks are referred to as “local” peaks. Each data window consists of a separate high and low
limit that are used from a given start angle to a given end angle.
The tonnage graph in Figure 3.5A is for a two station die. The first station cuts out the part (local peak),
and the second station stamps a logo onto the part (absolute peak).
Since the tonnage required to coin the logo is greater than the tonnage required to cut the part, the local
peak is not checked using a normal peak tonnage monitor. The local peak could completely disappear
and a normal peak tonnage monitor would not detect any anomaly in the process since the absolute peak
limits are still being satisfied by the coining part of the die. This is exactly what would happen if the
material did not feed between strokes as shown in Figure 3.5B. Using a single data window, however,
places a separate high and low limit on the local peak.
Section 3.2.1 Data Window On Angle
The On Angle for a data window is the angle at which the setpoints for that data window start to be
enforced. For example, in Figure 3.5, data window 1 has an on angle of 165 degrees.