Sequoia LISST-Hydro, Руководство пользователя

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If the concentration is within the acceptable level, a measurement of
the detailed size distribution will be made and the data will be
transmitted to the PC for processing and display. If the concentration is
higher than acceptable levels an accurate measurement of
concentration and size distribution cannot be made. In this situation a
dilution of the turbid water will be performed.
Capture sample
and dilute
If the concentration of the sediment is determined to be too high a
sample capture and dilution must be performed. To capture a sample
the values above and below the optical cell are closed. This trapped
known volume of water is then recirculated with a known volume of
clean water. This procedure performs a 15 to 1 dilution of the turbid
water.
The diluted turbid water is then recirculated through the optical cell
where a measurement of detailed size distribution if performed. Once a
measurement of detailed size distribution and concentration is obtained
the results are transmitted to the PC for processing and display. The
system then prepares itself for the next sample by flushing out the old
sample and rinsing with clean water.
System
Flushing and
preparation for
next sample
After obtaining a measurement the system must reset itself before the
next sample can be measured. The steps performed will vary
depending on if a sample dilution was performed.
If a dilution was not performed the preparation for the next sample is
simply to check the water level in the external water tank and fill the
dilution chamber as needed.
If a dilution was performed a series of flushing cycles will be performed
to make sure there are no residual particles remaining in the system
that would bias the next diluted measurement.
Upon completing the flushing procedure the system is now ready to
accept commands from LISST-Infinite software.