Kongsberg EA640, Руководство по установке

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Reducing propeller noise
• Each transducer must be installed as far away from the propellers as possible.
• Sufficient clearance between the propellers and the hull, the rudder and the keel must
be provided.
• Place the zinc alloy anodes in places where the water flow is the least disturbed.
• Ensure that the propellers blades are correctly designed and without damages.
• The use of a baffle between the propellers and the transducer may reduce noise
appreciably.
• Static discharges caused by the rotating propeller shaft may be removed by proper
grounding or by mounting a coal brush from the shaft to vessel ground.
Reducing rattle noise
Ensure that no parts near the transducers can rattle as a result of water flow or vibrations.
Reducing interference
Interference from the transmission pulses from other hydroacoustic instruments on
board the vessel is difficult to avoid. The problem may be reduced by choosing the
working frequencies carefully and to some extent by separating the different transducers.
On vessels with a large number of separate hydroacoustic systems installed and in
simultaneous use, a separate synchronizing system (for example the K-Sync) should
be considered.
Reducing electrical noise
• Place the transducer cables in a metal conduit from the transducer to the WBT.
Terminate the conduit as close to the transducers and WBT as possible.
• Make sure that all units are properly grounded, as this is important to avoid electrical
noise.
• Use shielded cables with correct grounding.
• Separate EA640 cables from other cables with high voltages, large currents or
transients. Place all high voltage power cables in metal conduits.
Preparations