LINK Systems OmniLink 5000 - Manual (Page 21)

April 17, 2000 Man ual Revisio n 1.0
3.6
Section 3.3.4 Reverse Limits
A Reverse Limit should be set more negative than the maximum reverse tonnage developed when
properly producing a particular part and is set for each channel of the tonnage monitor for the peak
tonnage only. Data windows do NOT have reverse limits associated with them. If something in the
process changes during normal operation that causes the tonnage developed to exceed this maximum
reverse limit, a Top Stop Signal is provided to the press control in order to stop the process. Excessive
reverse tonnages are damaging to the machine frame and reverse tonnage limits are active during the
entire working portion of the stroke.
Section 3.3.5 Total Tonnage Limit
There is only one limit that can be applied to the total tonnage. If so configured (see section 5.2 for
details), the machine rating derate table will apply a limit to the total tonnage that varies with the crank
angle (related to height off the bottom of the stroke). The machine rating is specified by the press
manufacturer at a specific height off the bottom of the stroke (typically .25 inches). Above this height
the total tonnage available is limited by the torque of the crankshaft and clutch and will decrease as the
height off the bottom at which the tonnage occurs increases. The machine rating derate table tells the
tonnage monitor how to limit the total tonnage. A Cycle Stop will be generated if this limit is exceeded.