Simrad ES70 - DOWNLOAD AND INSTALLATION REV B, Руководство оператора

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Display views
Pelagic echogram
The pelagic echogram appears very similar to the surface echogram. However, the
biomass calculations are not limited by the bottom detection.
Example 7 Start Range in a pelagic echogram
In a pelagic echogram, set the
Start Range
value to 20 meters. This will make
the echogram start from 20 meters below the sea surface (provided that the
transducer offset has been defined). Set
Range
to 40 meters. The echogram
will now show the area from 20 meters below the sea surface, and down to
60 meters below the transducer. Provided that the depth is larger than 60
meters, the bottom contour is not shown.
The biomass calculations are not restricted by the bottom detection. This means that the
bottom echo will be included in calculations if it appears within the chosen range.
Trawl echogram
The echogram covers the vertical opening of the trawl with reference to the depth of
the headrope.
In addition to the trawl opening, the echogram covers a certain range over and under the
trawl opening. This range is set by adjusting the
Range
and
Start Range
parameters.
Trawl sensor systems (typically Simrad ITI and PI) communicate headrope depth, as
well as the distance from the headrope to the footrope (trawl opening), to the ES70 at
regular intervals. This information is required for the trawl echogram to be generated.
Without the depth of the headrope, the echogram will appear like a standard pelagic
echogram controlled by the
Range
and
Start Range
parameters.
The distance from the headrope to the footrope (trawl opening) can be manually set
in the
Trawl
dialog. This is useful for trawl sensor systems not measuring the trawl
opening, or when the measured distance is unreliable. The
Trawl
dialog also allows you
to enter the distance from the vessel to the trawl opening. The depth of the headrope
must however be provided by the catch monitoring system.
In the
Trawl
dialog you can also define the distance from the vessel to the trawl opening.
Example 8 Start Range and Range in a trawl echogram
In a trawl echogram, set the
Start Range
value to –5 meters. This will make
the echogram start from 5 meters above the headrope. If the trawl opening is
20 meters, set
Range
to 30 meters. The echogram will now show the area
from 5 meters above the headrope, down across the trawl opening, and down
to 5 meters below the footrope. On a pelagic trawl, the bottom contour is
normally not shown with these settings. On a bottom trawl, the bottom
contour is shown once the trawl opening is less than 5 meters over the bottom.
The biomass calculations in a
Trawl
echogram are not restricted by the bottom detection.
This means that the bottom echo will be included in the calculations if it appears within
the chosen range.
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