HBM MP85A Operating Manual page 56

56
Thresholds
Thresholds monitor the process continuously in very restricted ranges. The
thresholds can be positioned vertically or horizontally. As an option for
machine safety, these evaluation elements can also monitor the process in
real time and signal the control via a digital output or the field bus.
y
Fig. 6.9: Thresholds
Envelope curve
The envelope curve continuously monitors the process in max. 4 adjustable
ranges. The process must enter the envelope curve on the one side and exit
on the other. The tolerance width of the envelope curve is freely selectable
and can therefore be adapted to process requirements. Evaluation takes
place at the end of the process.
y
Fig. 6.10: Envelope curve
Tolerance band
The tolerance band covers the complete process. The first to last measure-
ment points must lie within the tolerance band in OK processes (in contrast to
the envelope curve which must be entered and exited). Evaluation takes place
at the end of the process.
HBM
x-threshold
MP85A process controller
y-threshold
x
x
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