Mace HVFlo XCi, Руководство по эксплуатации продукта

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NOTE: Greyed area, not represented in actual real-time graph
“Gravity method”
This method should be used wherever a
stream is slow moving and/or contains few
acoustically reflective particles. Because
this calculation method is designed to
enhance the velocity processing of slow
moving/clean streams, it may also result in erroneous velocity readings unless enabled correctly. When
enabled, this method will display two new menu items.
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.“ Minimum stream activity ” - Under conditions of zero flow within a conduit (see maximum
measurement count) a single aquatic life form can produce large Doppler shifts. The minimum stream
activity parameter must be set to negate the effects of these aquatic life forms. This parameter should
be set to low values (2-10) in sites where extremely slow average velocities are expected (< 0.2 m/s).
Values greater than 10 can be set where average velocities of >0.2 m/s are expected.
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“
Stream activity percentage
” - To be used in conjunction with the minimum stream activity
parameter, this parameter forces the instrument to utilise only those velocity spectra that have a
minimum stream activity value greater than set by the user. Under good acoustic conditions typically
90 –100% of the data received by the velocity sensor will be used to calculate an average velocity.
Under conditions where the data received by the velocity sensor has been caused by aquatic life,
typically <10% of the data will be used. Therefore, this parameter should be set to low values (2-10) in
sites where extremely slow average velocities are expected (< 0.2 m/s). Values greater than 10 can be
set where average velocities of >0.2 m/s are expected.
WARNING: The user MUST check that the value entered for both “Minimum
stream activity” and “Stream activity percentage” do not cause real velocity
data to be ignored
MACE XCi User Manual - 160 -