Campbell Scientific OBS-5+ Sediment Concentration Monitor and Pressure Sensor - Manual (Page 34)

OBS-5+ System
5) Enter 0.001 in the value box and click the Record button to log the clear-
water data point. The unit will take 1,200 measurements in 60 seconds.
When the process is complete, the data appear in the data table and the ND
(red) and FD (green) points will be plotted on the calibration graph. If you
are satisfied with the data, mount the unit in the suspender.
6) Position the OBS-5+ so that it produces the minimum FD signal in clear
water (FIGURE 7-4).
FIGURE 7-4. OBS-5+ in suspender tub
7) Weigh the first increment of sediment with the electronic balance (see
TABLE 7-1) and transfer it to a tea cup with a rounded bottom.
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