Biral SWS-100-LW: SWS-200-LW, User Manual

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Maintenance Procedures Section 4
38
User Confidence Checks
Step 5 . Send the command: R?
Step 6
. Verify that the 'Transmitter Window Contamination' field value is much
greater than 10 (eg 99).
Figure 4-1 Transmitter hood with white card
Step 7
. Remove the white card.
4.3.3 Receiver Background Brightness Measurement Checks
The receiver background brightness value measures the optical signal detected by
the receiver caused by the intensity of the ambient background. This value is used
to set the threshold values for precipitation particle detection and interpretation.
The following procedure will check this function (this procedure is used for both
the forward scatter and backscatter receivers). For the SWS-100 – LW only carry
out the forward scatter test.
Step 1 . Insert grey foam plugs (‘Zero Plugs’, supplied in the calibration kit) into
the forward scatter receiver hood (and back scatter hood if applicable),
blocking all light from the window.
Step 2 . Send the command: R?
Step 3 . Verify that the value in the 'Forward (Back) Scatter Receiver
Background Brightness' field in the sensor response (see section 3.1.1) is
less than 00.06.
Step 4 . Remove the zero plugs from the Sensor Head receiver hoods.
white
card