Details

Boards

A graphic presentation of the transceiver boards is provided. The visual presentation reflects the physical location of the boards in the Transceiver Unit.

To select a transceiver board, click the "button". The corresponding transducer elements are identified.

Each button provides a small colour coded indicator.

• 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.

Transducer Elements

Each of the individual elements in the transducer is shown in a grid. The presentation attempts to organize the elements in the same manner as in the physical transducer.

Individual transducer elements may be disabled or enabled. To do this, right-click on the corresponding rectangle, and use the short-cut menu. A disabled element is shown with a blue rectangle.

Disabling a single transducer element can be useful for a number of reasons.

• An element is weak or simply unserviceable.
• An element is creating a lot of noise.

Reception Test

Select Reception Test to start an automatic test of the individual transducer elements. For the reception test to start, the ST90 system must be transmitting (pinging). The reception test validates each element in the transducer.The test returns the results using colour codes.

• Green: The transducer element is fully operational.
• Red: The transducer element offers reduced performance.
• Black: The transducer element is not working ("dead").

For more information, observe the tooltip provided for each element rectangle.

A small number of unserviceable transducer elements are accepted, even for operational use. This is regarded as "graceful degradation�. The ST90 system offers a large number of transceiver channels. 12 identical transceiver boards are used. 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 ST90 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.