Selecting The Best Location - Interphase iScan V90 Operation Manual

Thru-Hull Transducer Installation
The thru-hull transducer is the recommended choice for larger
boats with in-board engines. Thru-hull mounting is usually
required on larger power and sail craft in order to find a
mounting location free of forward looking hull obstructions.
The iScan V90 must have a clear view of the water ahead as
it can not magically see through obstructions such as the
vessel's hull. Please read the following carefully before
starting the thru-hull installation. Normally, thru-hull
installations are performed by a professional in a boat haul-
out facility. We suggest you seek professional assistance
before attempting to mount this transducer.

Selecting the Best Location

The best location to mount the thru-hull transducer will vary
with the type of boat. Try to find a location with the smallest
dead rise angle to make installation easiest.
a. On displacement hulls (sailboats, trawlers, etc.) locate the
transducer about 1/3 aft along the waterline. Generally this
provides the best compromise between obtaining aeration-free
water and minimizing propeller noise. The iScan V90's
transducer can not see through aerated water and water near
the bow and near the keel can be quite aerated. Aeration of
the transducer can be minimized by keeping the transducer
mounted away from the keel and by not mounting too far
forward.
b. On sailboats, the transducer should be mounted where the
acoustic beam will not be shaded by the keel. A spot forward
of a fin keel is usually best. Try to find an accessible spot
with a minimum dead rise angle. Place the transducer where
it will not rest on the lifting strap when hauled.
c. On planing powerboat hulls, the transducer should be
mounted well aft and close to the keel to insure that the
transducer is in contact with the water at higher boat speeds.
* On I/O's, transducer mounting close to the engine usually
yields good results.
* On inboards always mount the transducer well ahead of the
propeller(s). Turbulence from props can seriously degrade
performance. (Thru-hull installation is recommended.)
d. Mount the transducer on the side of the hull where the
propeller is moving downwards. The upward motion of the
propeller generates pressure waves and pushes bubbles up
against the hull.
Suggested Thru-Hull
Transducer Locations
Fin Keel
L = waterline length
Displacement Hull
MOLDED FAIRING BLOCK
If you're installation requires a fairing block, you
may either have one made locally, or purchase a
molded plactic unit from Interphase or your
Interphase distributor.
For the T1-I200-026 Thru-Hull transducer, the
molded Fairing Block Part Number is:
42-2004-000
14
~ 1/3 L
Planing Hull