General Description of Functions
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The measured value for the leakage rate and the related quality assessment in percent are reset at the
start of every suction cycle and constantly updated during the cycle as moving averages. The values there-
fore remain stable until after the suction cycle is complete.
Measurement of dynamic pressure:
This measures the system vacuum achieved during unobstructed suction. The duration of the measure-
ment is approx. 1 second. Therefore, to evaluate a valid dynamic pressure, uninterrupted suction is re-
quired for at least 1 second after starting the suction, i.e. the suction point must not be covered by a part.
Measured values below 5 mbar or above the vacuum limit value H1 are not regarded as valid dynamic
pressure measurements and are rejected. The result of the last valid measurement is retained. Measured
values that are higher than the vacuum limit value (H2-h2) and simultaneously lower than vacuum limit
value H1 result in a condition monitoring event.
The dynamic pressure (vacuum during unobstructed suction) and the related performance assessment in
percent are initially unknown when the ejector is switched on. As soon as a dynamic pressure measure-
ment can be performed, they are updated and retain their values until the next dynamic pressure mea-
surement.
Quality assessment:
To evaluate the overall gripping system, the ejector calculates a quality rating based on the measured sys-
tem leakage. The greater the leakage in the system, the worse the quality rating of the gripping system.
Conversely, low leakage results in a high quality rating.
Performance calculation:
Similar to the quality assessment, the performance calculation is used to evaluate the system status. The
performance of the gripping system can be assessed based on the determined dynamic pressure. Opti-
mally configured gripping systems lead to low dynamic pressure and thus to high performance. Con-
versely, poorly configured systems result in low performance. Dynamic pressure events that exceed the
vacuum limit value (H2-h2) always result in a performance rating of 0%. A dynamic pressure value of
0 mbar (indicator that a valid measurement was not obtained) also results in a performance rating of 0%.
7.26.4 Diagnostic Buffer
The condition monitoring warnings described above and the general error messages from the device are
saved in an integrated diagnostic buffer. The content of this memory is made up of the last 38 events,
starting with the most recent, and can be read out via an IO-Link parameter. For each event, the current
reading of the suction cycle counter cc1 is also saved to allow subsequent temporal assignment of the
events to other processes in the system. See the associated IO-Link Data Dictionary for the actual data dis-
play of the diagnostic buffer. The recording of these events is also active in SIO mode and the contents of
the memory is retained after a power failure.
The memory is deleted manually using the IO-Link system command “Clear diagnostic buffer” or also by
restoring the factory settings on the device.
7.26.5 EPC Data Buffer
The ejector provides a ten-stage data buffer to enable long-term monitoring and trend analysis of the
most important key figures in a handling process. The current measured values for the evacuation time t1,
leakage rate and dynamic pressure (vacuum during unobstructed intake), which are determined during
the suction cycle, can be saved in this buffer. The values are saved automatically, always together with the
execution of the autoset function in the condition monitoring area described above. For each data record,
the current reading of the suction cycle counter cc1 is also saved to allow subsequent temporal assign-
ment to other processes in the system. The contents of the EPC data buffer can be read out via an IO-Link
parameter. See the associated IO-Link Data Dictionary for the actual data display of this buffer. The con-
tents of the memory remains intact after a power failure.
