• | 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. |
• | No indicator: Status is OK. No actions are necessary. |
• | Yellow: This is a warning. A closer investigation is recommended. |
• | Red: This is an alarm. A closer investigation is required. |
• | Blue: A device monitored by the diagnostic system is disabled. |
• | Grey: No information is available. |
1 | Make sure that you have sufficient water depth below the keel before you lower the transducer. |
2 | Lower the transducer to its bottom position. |
3 | Select the default settings.
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4 | Make the following preparations.
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5 | Select Transducer to open the page. The Transducer page presents all the elements that are used in the transducer. The presentation attempts to organize the elements in the same manner as in the physical transducer. The transceiver boards are shown as "buttons". Select a transceiver board to highlight the elements that are physically connected to the board.
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6 | Select Reception Test to start an automatic test of the individual transducer elements. The reception test validates each single element in the transducer, and returns the status using a simple colour code.
For more information, observe the tooltip provided for each element rectangle.
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7 | Make sure that the number of unserviceable ("dead") elements does not degrade the performance of the SU90 system. A small number of unserviceable transducer elements are accepted, even for operational use. This is regarded as "graceful degradation”.
The SU90 system 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 display 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.
Which actions to take if single channels fail depend on the operational impact, the overall performance of the SU90 system, and a cost/benefit assessment. The most important factor in the cost/benefit assessment is whether you need to replace the transducer, or just a single transceiver
board. If more than 3% of your transducer elements have failed, we recommend that you contact your dealer for advice.
Note
For further investigations of this issue, use the functionality offered by the Element BITE (Element Built In Test Equipment) dialog box.
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8 | 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.
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9 | Finish the test.
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• | 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. |
• | Check for environmental noise, such as other vessels in the vicinity or animal life. |