5 – Operational Considerations
DPN 402197 Issue 7.1
© Teledyne Limited
5- 1
5 Operational Considerations
5.1 Operating Performance
Together with the skilful operation of the 350 system, two major factors influence the response and the
performance of the system during survey operations:
1. Frequency of the target tone
You may minimise the effects of background noise by selecting a tone that is in a relatively quiet part of
the received band of frequencies. The Scope and Spectrum Analyser Window within DeepView helps
you make this selection.
2. Coil arrangement on the ROV
The performance of the 350 system depends heavily on the mounting arrangements of the coil array.
You need to consider two factors carefully when you use the system:
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Because the 350 system uses trigonometry to determine the target co-ordinates, the accuracy
of its survey measurements will improve with larger coil separation distances. However, by
installing the coil triads farther apart you might find it difficult to manoeuvre the ROV.
❐
Large masses of ferromagnetic material can distort the magnetic fields that the 350 system
uses to survey the target. There is usually an abundance of such materials in the ROV body.
You should install the coil array where it is at least 0.5 metres away from the ROV body. The
installation instructions provided in this manual describe a configuration of the 350 system that
combines ease of deployment with optimal performance.
Summary
:
The logged data packets include a Quality Control flag to identify data that might show degraded
accuracy.
Use all the information and facilities available from the 350 system to identify any drop in system
performance so that you may take effective and appropriate corrective action.
5.2 Sources of Error
There are other error sources that might degrade system performance. You should make yourself
aware of these so that you may take action to avoid them or to reduce their effect on survey results.
These error sources fall within two categories:
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ROV handling
❐
Electrical interference
5.2.1 ROV Handling
The following paragraphs describe the potential sources of error that might arise as a result of unskilled
or inappropriate operation of the ROV. These include:
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The relative positions of the ROV and the target
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ROV trim and skew