Bottom Detection; How To Define Maximum And Minimum Depth - Simrad ES70 - REFERENCE MANUAL REV A Reference Manual

Simrad ES70
Enter any value from the keyboard.
b

Bottom detection

These procedures explain how you can control the bottom detection.
Related topics
• About range selection on page 210
• About bottom slopes on page 209

How to define maximum and minimum depth

When you use the ES70 it is very important that the echo sounder detects and "locks" on
the correct depth. Normally this will happen automatically, but certain sea or bottom
conditions, or the appearance of large schools of fish, may "fool" the sounder. When the
bottom is undetected you will read 0.00 meters depth, or any other erroneous value. In
order to guide the ES70 to locate the correct depth, you may some times find it useful
to follow this procedure.
1 Click the
Active
Click
2
Bottom Detector
→ Bottom Detector on page 167
Enter a
3
Minimum Depth
This setting eliminates all unwanted bottom detections from the transducer surface
and down to the defined depth. A false bottom detection within this area would
cause erroneous depth read-out and incorrect bottom expansion.
4 Enter a
Maximum Depth
Set this depth to approximately 50% more than the expected depth. If the echo
sounder should loose bottom detection due to air or other disturbances, it will try to
relocate the depth within the minimum and maximum depths you have defined. Do
not exaggerate. If you for example enter 5000 meters and the bottom track is lost,
the echo sounder will search the entire depth for new bottom lock. This will take a
lot of time, and a lot of information will be lost during the search, especially during
rough sea conditions with air being forced under the hull.
76
icon under the menu to open the
Main
to open the
Bottom Detector
.
.
sub-menu.
Active
dialog.
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