Transducer Installation Using Drop Keel - Simrad EC150-3C Installation Manual

Preparations
Note
Make sure that the "Forward" direction on transducer points in the forward direction
of the vessel.
A suitable mounting ring can be provided by Kongsberg Maritime. A drawing is
available for local manufacturing. The drawing (normally in AutoCad format) can be
downloaded from our website.
• https://www.simrad.com
Smooth surface is important
Make sure that the surface of the transducer face, as well as the plating and putty around
the transducer is as even and smooth as possible. Obstructions on these surfaces will
create problems with turbulent flow, and may cause noise.
Mounting screws or bolts must not be extruding from the transducer or the plating
immediately around it.
Note
Obstructions on these surfaces will create problems with turbulent flow, and may cause
noise.
Related topics
Transducer installation principles, page 34
Installation summary, page 30

Transducer installation using drop keel

If your vessel is fitted with a drop keel, this is a superior platform for the EC150-3C
transducer.
Drop keels are often used on larger research vessels. A drop keel will frequently protrude
as far as three meters below the hull. At that depth, the water is free of air bubbles
up, even during very high sea states. The vessel is then able to do reliable acoustic
measurements in open sea a larger part of the year.
At the bottom of the drop keel, the EC150-3C can be installed with the transducer face
flushed with the horizontal plating. A protective tank may not be necessary, since the
drop keel will normally offer adequate protection.
The drop keel is normally used for several echo sounder transducers.
The transducer cable must be properly fastened at the bottom of the drop keel, and
supported during the lowering and lifting the drop keel.
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