Simrad Simrad SP70, Installation Manual

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Simrad SP70
24
851-164336 / D
2.2 Location of the Hull Unit
Fore and aft
The Hull Unit should preferably be located within 1/10 to 1/3 the
vessel’s Length Between Perpendiculars (LBP) measured from its
Forward Perpendicular (FP). Deviations from this rule should not
be made without consulting Simrad.
→
The location of the hull unit is indicated in figure 2.
Athwartships
The Hull Unit may be located on the Centre Line (CL) of the vessel,
or alongside its keel. If the installation is off-set from the vessel’s
centre line, make sure that transducer transmission and reception
will not be obstructed by the keel.
Welding marks
for docking
Waterline at normal trim
LBP
(CD1881)
1/3 to 1/10
LBP
90°
Figure 2 Location of the Hull Unit
Important considerations
The Hull Unit trunk must be installed so that it will be vertical
under normal operating conditions.
The primary sources of underwater disturbance (other than a
vessel’s main propeller and bow/sternthruster) that affect
transducer reception are:
•
Main or bilge keels
•
Zinc anodes
•
Cooling elements protruding from the hull
•
Equipment such as sonar transducers and pitot tubes
•
Sea chests