WÄRTSILÄ LAZ 5100, Техническое руководство

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Technical Manual LAZ 5100 / ES 5100
INSTALLATION, CARE AND MAINTENANCE
5-2 Technical Manual LAZ 5100 / ES 5100 TH 52 603 8001 EN Rev.: S
On ships equipped with a bulb bow, the transducer must be mounted as far as
possible ahead, because the bulb generates a layer of air bubbles that heavily
reduces the transducer / echo sounder performance.
A transducer mounted in the vicinity of the ship's stern can be operated only while
drifting, at the pier or at very low speed. The reason is that the stern area is generally
disturbed by turbulence and air bubbles, dependent on ship's speed. In addition,
vibrations and engine noise may be a source of disturbances. The sound signal
cannot penetrate this layer, the bottom echo fades away and the digital display shows
the zero echo (1 - 1.5 m) or "?". Therefore only the front transducer must be used
while sailing.
Once the transducer has been installed, the system must be set up to under
consideration of several factors:
These are:

Transducer installation depth beneath the surface.

Transducer installation height relative to the lowest part of the ship's keel.

Blocking depth, a setting to prevent false digital depth readings caused by
resonance of non-ELAC transducers
. This setting needs not to be altered from
ZERO if using ELAC transducers.

Frequency of the transducer.

Installation position of the transducer, e.g. BOW, AFT, Pt., Stb, (if two transducers
are installed).
When a transducer is installed, i.e. before the ship is launched, measure the height
difference between the radiating surface of the transducer and the lowest part of the
keel and the distance between the waterline and the radiating surface of the
transducer. These measurements are necessary to compensate the differences when
the system is initially set up. The transducer frequency is shown in the shipping
documents.
Connect the system in accordance with the connection diagram (see chapter 6).
When cabling the system, take special care that all signal lines are screened properly.
The cable from the transducer to the connection box must be laid in a steel pipe.
From the connection box to the echo sounder there are the following choices for a
proper cable laying:

the transducer cable is laid within a steel pipe, that is connected to the ship’s
ground.

a double-screened cable is used as transducer cable, the inner screen is one-side
connected to the echo sounder's ground, the outer screen is connected to the
ship's ground on both sides ( see Figure 5-1).
The transducer cable is laid at least 0,5 m apart from all other cables.
By no means a single-screened cable must be laid together with any other cable.