Burster DIGIFORCE 9311, Руководство по эксплуатации

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3.8 Sensor test
Regular checking of sensors plays a crucial role in the test reliability of a quality control system. In these
checks, defined physical quantities are applied to the sensors. The DIGIFORCE
®
9311 then evaluates the
resultant electrical signals.
An example of how to calibrate these values is to use a feed unit to move into a reproducible position
such as the top limit of travel for the press, or up to a master part. In this position, the DIGIFORCE
®
9311
captures the channel measurements and applies tolerance limits to these measured values.
Then measurements are performed again precisely at these positions in the regular sensor test. The
sensor test, initiated by a PLC signal ("IN_STEST"), checks the sensor values at these positions. If a
sensor lies outside the tolerance range, DIGIFORCE
®
9311 sends a warning signal to the PLC
("OUT_OK_ STEST" = 0). This practically eliminates any erroneous measurements from faulty or drifting
sensor systems.
3.9 Online switching points
The online switching points can be used to output in real time a signal at the control interface (PLC I/O or
Fieldbus) if a set signal level is exceeded. Switching points S1 to S6 are provided for this function. You
are free to choose their switching polarity and can assign them to the X and Y measurement channels as
you wish.
When assigning a switching signal to the X-channel, you can choose to refer the set level (threshold
value) to the absolute zero point ("Absolute" reference) or to a relative zero point ("Trigger" reference).
These switching points are updated in real time both during and outside an active measurement cycle.
3.10 Visualizing, signalling and transferring results
The DIGIFORCE
®
9311 shifts immediately into the evaluation phase at the end of a measurement. In this
phase, the unit checks whether the measurement curve meets the conditions of the graphical evaluation
elements such as a window or envelopes. If the conditions are met, the DIGIFORCE
®
9311 assesses the
measurement as OK. If, however, it identifies an infringement of the graphical evaluation elements, it
assesses the measurement as NOK.
In parallel with updating the global OK/NOK result at the end of the measurement, the DIGIFORCE
®
9311
also refreshes the active measurement window in the display. In addition, it updates the relevant PLC I/O
signals and also any status signals and result values at the Fieldbus interface. Once a measurement has
finished, you can retrieve curve data and measurement results via the communications interfaces
(Ethernet and USB). You can also use the DigiControl PC software to log this data automatically after
every measurement. This process can also run synchronously on more than one DIGIFORCE
®
9311 unit
at once. In addition, you can log the data on a USB stick and display the most recent measurements in
the "Graphical Curve analysis" menu (M70).