Furuno FSV-85 Installation Manual page 11

1.1.2 Guideline for how to shorten the retraction tank
Shorten the tank as necessary so that the transducer positions well below the keel
when it is fully lowered. The following table provides guidelines for shortening the tank.
Refer also to the retraction tank installation drawing at the back of this manual.
Installation
Method
Stroke
800 mm
stroke
1100 mm
stroke
Note 1: The transducer will lower to mid-protrusion (500/800 mm stroke) if the tank is
not shortened. However, if it is shortened more than 50 mm, the transducer cannot be
completely retracted.
Note 2: When maximum length is removed and "D" is minimum, the effect of air foam
is minimized because the transducer fully protrudes in water.
Guideline for the installation of the retraction tank
• Install, if possible, the tank on the keel where the tank can be most firmly fixed.
• Install the reinforcement ribs as near as possible to the top of the retraction tank,
allowing space for tightening of nuts and bolts.
Retraction tank
250-300 mm
• Fit a doubling plate (a plate added to another to give extra strength or stiffness) of
700 mm diameter to the location where the retraction tank is welded to the hull bot-
tom. See the outline drawing at back of this manual.
Cut
0-50 mm
from the
Same as left.
end.
Cut
0-50 mm
from the
Same as left.
end.
1. HOW TO INSTALL THE SYSTEM
D
Cut 0-50 mm
from the end.
Note that the length
"D" must be less than
1000 mm.
Cut 0-50 mm
from the end.
Note that the length
"D" must be less than
1200 mm.
Reinforcement rib
No. of ribs: Minimum 4
Thickness: at least 12 mm
D
Same as left.
Same as left.
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