Simrad SU90, Приемо-сдаточные испытания в порту

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The SU90 operates with 384 individual channels handled by 12 transceiver boards.
If a single channel fails during normal operation, you are not likely to detect it.
Even if several channels fail, you may not see it.
The detection of a faulty channel depends on the physical location of the relevant
transducer element. If faulty channels are grouped together on the transducer face,
this may cause a visible defect in the SU90 presentation. If they are scattered,
the visible defect may be a lot harder to see. In all cases, the echoes from the
neighbouring channels cause an interpolation that will restore a lot of the degraded
presentation.
Note
For further investigations of this issue, use the functionality offered by the
Element
BITE
(Element Built In Test Equipment) dialog box.
10 If the result from the reception test shows a number of transducer elements that are
either defective or offer reduced performance, repeat the test.
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.
Excessive noise or interference may be misinterpreted as physical defects.
You may need to repeat the test several times, and - if necessary - implement a
"silent ship" to improve the conditions.
11 Finish the test.
a Close the
BITE
(Built In Test Equipment) dialog box.
b Set
Tx Power
to Off .
c Hoist the transducer back up to its upper position.
Result
Requirements
Results
The maximum number of unserviceable elements is 4.
Date and signature:
Further requirements
If the noise level is higher than specified, you must check the reason(s) for this.
• Check the grounding of the Transceiver Unit.
• Verify that other electric equipment and/or machinery on board, such as cooling
systems, hydraulic pumps, electric motors etc, do not influence on the noise reading.
Switch off as much machinery as possible, especially electrical motors.
• Check for interference from other hydroacoustic systems.
Simrad SU90 Harbour Acceptance Test