Kongsberg EM 710, Installation Manual

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Transducer arrays
4.1.2 Installation philosophy
The EM 710 Multibeam echo sounder is supplied as a basic
echo sounder with two relatively large transducers. While the
electronic units are installed using normal tools, the transducer
arrays must be located and installed depending on the vessel’s
design. A number of different factors related to the vessel’s
design must be taken into consideration during the installation
planning.
The basic installation methods are:
• Gondola
• Blister
• Flush-mounted integrated into the hull
• Externally mounted with fairing(s)
• In a box keel
• Any combination of the above
See chapter Installation examples on page 43
A fairing will usually be added around the transducers to ensure
laminar water flow without any aeration problems. A blister or
gondola installation may help in avoiding air bubble blockage of
the sound path under the transducers by aerated water. Blisters
and gondolas may also contain additional transducers for other
systems.
Normally, in a permanent installation, the cables enter the
hull through tubes which are fitted with standard ship type
cable glands (Brattberg, Roxtec or equivalent) to provide water
tightness. The cable glands should be of the type having a
pressure rating of 4 bars or more. If the tubes end below the
vessel’s water-line, classification requirements may require a
double set of glands.
The installation of the transducer arrays must thus be planned
together with the installation shipyard and/or the client.
Once the installation method is defined, the installation shipyard
must provide the necessary drawings. These drawings must be
approved by the vessel’s classification authority.
If required, Kongsberg Maritime AS can assist with the required
engineering.
4.2 Installation steps
The following steps must be taken to install the EM 710
transducer arrays:
1 Determine the physical location of the transducer arrays
under the vessel’s hull.
Locating the transducer array on page 31
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