Banner DF-G1-PR-Q7 Instrucciones de operaciones Pagina 137

  • Descarga
  • Añadir a mis manuales
  • Imprimir
  • Pagina
    / 253
  • Tabla de contenidos
  • MARCADORES
  • Valorado. / 5. Basado en revisión del cliente
Vista de pagina 136
350 Cable Survey System
DPN 402197 © TSS (International) Ltd Page 26 of 30
7.5.2.2 Electrical Interference
The 350 System is unaffected by the following factors:
Changes of ROV heading
Any local static magnetic field
Acoustic noise
The presence of platforms, rigs or other vessels in the vicinity.
This sub-section describes the sources of interference that might affect the 350 Sys-
tem.
You may estimate the level of background noise by examining the Scope and Spec-
trum Analyser window of DeepView. If the noise level is so high so that it masks the
tone frequency, take whatever action you can to reduce or eliminate the noise.
The ROV
Other items of electrical equipment on board the ROV, for example the thrusters,
might represent a powerful source of electrical noise. If these noise components are
at a sufficiently high level, they might mask the relatively weak signals associated with
the target tone.
Signal discrimination by the 350 System is extremely good. It removes noise from the
calculation process by examining only a very narrow window of frequencies with the
tone at its centre. However, where noise levels centred on the tone frequency are
very high, they might degrade the performance of the 350 System and affect the
accuracy of its survey measurements.
The Scope and Spectrum Analyser window of DeepView will show those bands
where noise is at a minimum. You may then adjust the frequency of the target tone to
fall within one of these quieter bands.
Summary:
Use the SDC display software to check all channels of the 350 System with all electri-
cal equipment on the ROV operating. Select a tone frequency centred on a part of the
band that has low noise levels.
Investigate any severe noise sources before you start the survey and reduce or elimi-
nate them if possible.
Use the display software to perform regular checks on the quality of tone signal.
Vibration
Mechanical vibration of the coil triads could create a noise signal at a relatively low
level as the coils move relative to local magnetic fields. This noise would exist across
a broad band of frequencies centred on the frequency of vibration.
Vista de pagina 136
1 2 ... 132 133 134 135 136 137 138 139 140 141 142 ... 252 253

Comentarios a estos manuales

Sin comentarios