Transducer Installation In A Blister - Simrad EC150-3C Installation Manual

Transducer installation in a blister

In order to install a transducer with a circular housing, one recommended installation
method is by means of a blister. The blister must be designed and manufactured by the
installation shipyard to fit the transducer, as well as the vessel's size and hull shape.
The transducer may be added to an already existing blister that also holds other flush
mounted transducers.
Illustration:
Blister
A
Mounting ring
B
Cable service loop
C
Transducer
D
Clamping ring
E
Bolt
F
The best performance is
obtained with a blister height of
40 cm or more. A streamlined
shape and rounded edges
reduce the flow noise. A
vertical leading edge or front
will guide the aerated water to
the sides of the blister.
The orientation of the blister
should follow the water flow.
The interior of the blister
must be filled with sea water.
Use drainage holes in the
bottom and an air outlet on the top. The water pressure behind the transducer will then
compensate for the outside pressure during vessel movements in rough sea. This is an
important security precaution to prevent damage to the transducer.
The transducer cable penetrates the hull using a cable gland. This cable gland consists of
a bushing, washers, a rubber gasket and a packing nipple. Leave an adequate loop of
the cable over the transducer body inside the blister for easy mounting or removal of
the transducer.
438371/A
Preparations
35