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9 – Maintenance
9-4
© Teledyne TSS
DPN 402196 Issue 4.1
9.1.2 Sub-sea Electronics Pod
The SEP includes three circuit boards:
❐
Main Board
❐
Driver Board
❐
Analogue Board
9.1.2.1 Main Board
(
See drawings 401178 and B929935 in
NOTE
The main board assembly (401183) comprises the main board (401178) with an
integral piggy-back board (B929934). The spares part is 401183 which incorpo-
rates the integral piggy-back board.
The SEP drives the coil channels sequentially with control exercised through a Programmable Timer
under the direction of a high-performance Digital Signal Processor (DSP) on the Main Board.
After amplification, the signals from each channel pass to the analogue-to-digital converter (ADC) and
then to the DSP. The DSP performs the complex signal analysis necessary to determine the target
position.
Finally, the Main Board sends the target co-ordinates to the SDC through an optically isolated serial
communications link.
9.1.2.2 Driver Board
(
See drawing 401181 in Section
)
Under the control of the Main Board, the Driver Board drives the coil channels using four power
MOSFET switches.
A current limiter allows coil current to rise to a maximum value of 20A during each drive pulse. The
action of the limiter ensures that the amplitude of the current pulse is substantially independent of any
variations in the supply voltage arriving at the PSU.
At the correct moment during each measurement cycle, the Driver Board switches off coil drive current.
At this moment, the current in the coil falls very rapidly towards zero causing a back e.m.f. that drives
the associated MOSFET briefly into avalanche breakdown at 250V.
Refer to Appendix A for details of the operating theory and the timing for each measurement cycle.
An LC filter smoothes the current drawn from the PSU to an approximately continuous level (
not
RMS)
of 7A (with three search-coils attached).
9.1.2.3 Analogue Board
(
See drawing 401071 in Section
)
Содержание 440
Страница 12: ...List of Figures x Teledyne TSS DPN 402196 Issue 4 1 ...
Страница 16: ...Revision History xiv Teledyne TSS DPN 402196 Issue 4 1 1 0 Feb 19 2003 First Issue Issue No Date Details ...
Страница 18: ...Glossary xvi Teledyne TSS DPN 402196 Issue 4 1 ...
Страница 24: ...1 Introduction 1 6 Teledyne TSS DPN 402196 Issue 4 1 ...
Страница 32: ...2 System Overview 2 8 Teledyne TSS DPN 402196 Issue 4 1 ...
Страница 66: ...4 Electrical Installation 4 20 Teledyne TSS DPN 402196 Issue 4 1 ...
Страница 88: ...5 Operating Software 5 22 Teledyne TSS DPN 402196 Issue 4 1 Figure 5 10 Altimeter Test ...
Страница 144: ...6 Operating Procedure 6 40 Teledyne TSS DPN 402196 Issue 4 1 ...
Страница 154: ...7 Operational Considerations 7 10 Teledyne TSS DPN 402196 Issue 4 1 ...
Страница 164: ...8 System Specifications 8 10 Teledyne TSS DPN 402196 Issue 4 1 ...
Страница 203: ...10 System Drawings DPN 402196 Issue 4 1 Teledyne TSS 10 17 Figure 10 15 SDC10 Dimensions ...
Страница 204: ...10 System Drawings 10 18 Teledyne TSS DPN 402196 Issue 4 1 Figure 10 16 400604 1 Power Supply Chassis Assembly ...
Страница 205: ...10 System Drawings DPN 402196 Issue 4 1 Teledyne TSS 10 19 Figure 10 17 400667 1 Main Chassis Assembly ...
Страница 206: ...10 System Drawings 10 20 Teledyne TSS DPN 402196 Issue 4 1 Figure 10 18 400667 2 Main Chassis Assembly ...
Страница 209: ...10 System Drawings DPN 402196 Issue 4 1 Teledyne TSS 10 23 Figure 10 21 400654 1 PSU Filter Assembly ...
Страница 210: ...10 System Drawings 10 24 Teledyne TSS DPN 402196 Issue 4 1 Figure 10 22 490232 1 Processor Pod Assembly ...
Страница 211: ...10 System Drawings DPN 402196 Issue 4 1 Teledyne TSS 10 25 Figure 10 23 490228 1 Power Supply Pod Assembly 110v version ...
Страница 212: ...10 System Drawings 10 26 Teledyne TSS DPN 402196 Issue 4 1 Figure 10 24 500045 1 Coil Mounting Frame ...
Страница 213: ...10 System Drawings DPN 402196 Issue 4 1 Teledyne TSS 10 27 Figure 10 25 B930892 1 Coil Assembly ...
Страница 214: ...10 System Drawings 10 28 Teledyne TSS DPN 402196 Issue 4 1 Figure 10 26 601004 1 Coil Cable Assembly ...
Страница 215: ...10 System Drawings DPN 402196 Issue 4 1 Teledyne TSS 10 29 Figure 10 27 B930473 1 PSU to ROV PWR COMMS Cable 3 0m ...
Страница 230: ...A Operating Theory A 12 Teledyne TSS DPN 402196 Issue 4 1 ...
Страница 242: ...B Options B 12 Teledyne TSS DPN 402196 Issue 4 1 ...
Страница 244: ...C Altimeter C 2 Teledyne TSS DPN 402196 Issue 4 1 ...
Страница 246: ...D Reference D 2 Teledyne TSS DPN 402196 Issue 4 1 ...
Страница 248: ...D Reference D 4 Teledyne TSS DPN 402196 Issue 4 1 ...
Страница 250: ...D Reference D 6 Teledyne TSS DPN 402196 Issue 4 1 ...
Страница 252: ...D Reference D 8 Teledyne TSS DPN 402196 Issue 4 1 ...
Страница 254: ...D Reference D 10 Teledyne TSS DPN 402196 Issue 4 1 ...