1.3.1 Mounting Location
To decide the location of the transducer, the following points should be taken into account.
•The most important matter is where the transducer is installed. The position should be free from aeration possibly occurring beneath the hull and also not affected by engine and propeller noise.
•It is known that air bubble streams start approximately from a quarter length from the bow, and spreads over the hull bottom approximately to three quarters. Air bubble streams vary in form and intensity according to ship's speed, draught, trim, shape of bow and hull, as well as sea state.
•In a laden ship, a position somewhere near a quarter of the ship's length from the stern often gives satisfactory results. As for vessels such as oil tankers whose fore draught is especially shallow, an after position about three quarters of ship's length from the stern is often suitable.
•It is recommended to install the transducer on the keel line or between 600 mm and 900 mm from the keel to minimize the effect of aerated water.
•Sitting near obstructions such as the forward propeller, bow thruster, water intake pipes and speed log sensor should be avoided.
•Select a place giving minimum mechanical vibration.
•Do not lay the transducer cable near or in parallel with other electric cables.
1.3.2 Example of Transducer Installation (TTF-5600)
Note: Never fail to remove the transducer and rubber gasket prior to welding the transducer tank to the hull.
1.Install the transducer tank on the hull. The tank bottom should be flush with the hull bottom. Feed the transducer cable through the cable gland.
2.Apply sealing tape to the threads of the gland nut for watertightness.
3.Pass the cable thru the gasket, washer and gland nut.
4.Fix the transducer to the tank with the transducer fixing flange.
5.Coat the gland nut with silicone grease.
6.Tighten the gland nut.
5