Kongsberg Simrad MF90, Installation Manual

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476671/B
201
Starting up the hull unit
Topics
Hull Unit description, page 201
Hull unit familiarization (MF90), page 204
Hull unit familiarization (MF94), page 205
Motor Control Unit familiarization, page 206
Initial safety check of the Motor Control Unit, page 207
Checking the hosting motor’s 3-phase AC connections, page 208
Connecting the 3-phase AC power to the Motor Control Unit, page 210
Venting the transducer shaft sleeve, page 211
Checking the 3-phase connection for correct rotation, page 212
Checking the operation of the Hoisting and Lowering contactors, page 214
Checking the transducer lowering and hoisting functionality, page 216
Hull Unit description
The hull unit is used to lower the transducer down below the ship’s hull when the MF90
system shall be used. When the MF90 system is turned off, the transducer is hoisted for
protection. The hull unit is large and crucial part of the sonar system.
The hull unit is a mechanical construction. It is mounted on the top of the installation trunk.
The installation trunk penetrates the ship’s hull, and allows the transducer to be lowered into
the sea. The hull unit is normally located in the forward part of the vessel. This location is
recommended to avoid the noise from the propellers and the engine.
Caution
When the transducer is lowered, the depth of water under the vessel must be monitored
closely.
If the transducer hits larger objects or bottom, the transducer shaft may be bent, or - in
worst case - it can be broken off. A broken transducer shaft will cause water leakage
through the top of the shaft. If you suspect that the transducer shaft is seriously damaged
with holes, do not retract the transducer to its upper position.
To prevent serious damage to the vessel or the vessel stability, you must have a water
pump and a warning system in the sonar room.
Setting to work