Product Description
DUSTHUNTER T · Operating Instructions · 8012428 V2.2 · © SICK AG
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Control value measurement (Span test)
Sender beam intensity changes between 70 and 100% during control value determination.
The light intensity received is compared against the standard value (70%). The measuring
system generates an error signal for deviations greater than ±2%. The fault message is
cleared again when the next functional check runs successfully. The control value is
determined with high precision through statistical evaluation of a high number of intensity
changes.
Contamination measurement (not on DUSTHUNTER T50)
The glass panes positioned in the sender beam during normal measurement are swiveled
away during contamination determination. The measured value determined and the value
defined during scaling are used to calculate a correction factor
. This fully
compensates any contamination that occurs.
Contamination is determined on one side on the DUSTHUNTER T100 (pivoted shutter only
on the sender/receiver unit) and on both sides on the DUSTHUNTER T200 (pivoted shutter
also on the reflector).
Figure 4
Contamination measurement principle (on both sides)
An analog value between live zero and 20 mA proportional to contamination is output
during the check cycle for contamination values < 30%, (DUSTHUNTER T100) or 40%
(DUSTHUNTER T200); when this value is exceeded, the "Malfunction" status is output (for
the fault current set on the analog output for this case;
,
Figure 5
Pivoted shutter settings on the sender/receiver unit
Sender/receiver unit
Reflector
Pivoted shutter
Measuring position
Contamination measurement
Glass pane
Control
reflector
(only on the
sender side)
Pivoted
shutter
