Kongsberg Simrad MF90, Installation Manual

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476671/B
323
Result
Requirements Results
The information presented by the
B-Scan
page verifies that the MF90 system is
fully operational.
All elements are operational in both transmit and receive. The maximum
number of bad elements is: 3
Weak elements:
Unserviceable elements:
Date and signature:
Measuring the noise in passive mode
Low noise is a key factor for high quality and reliable measurements. The performance of
the MF90 system will always be limited by different noise sources. A high noise level will
mask the echoes and make them difficult to read and interpret. The noise is measured while
the MF90 system operates in
Passive mode with the transmit pulses disabled.
Prerequisites
The MF90 system is turned on and operates normally.
• The MF90 system is in Normal mode, but
TX Power
is set to Off to prevent transmissions.
• The transducer is retracted to its upper position.
• Neither tools nor instruments are required.
In order to do this test, the ship must be "silent".
• The water must be as deep as possible. Recommended minimum depth is 100 metres.
• There must be no other vessels in the vicinity.
• The vessel must lie still in the water.
• As much machinery as possible must be turned off. It is particularly important to turn
off electrical motors, as well as cooling systems and hydraulic pumps that may cause
electric noise.
• To prevent interference, all other hydroacoustic instruments must be turned off.
Note
With the vessel in port, the environmental conditions are not satisfactory. In the shallow
waters of the port, noise from other vessels, dockyard workers or machinery will cause
unreliable test results. If you do this tests in a busy harbour, or with noise sources present,
the sensitive receivers will detect all the noise in the nearby waters.
Setting to work