Electrical fault location determination

1. A method of determining the location of a fault in a cable at an underwater fluid extraction facility, the method comprising:

providing a time domain reflectometry unit at the facility, the unit being connected to at least one wire within the cable;

causing the unit to transmit a current pulse to the wire;

detecting a reflected pulse received at the unit;

determining the time duration between the pulse transmission and the reflected pulse reception and using the duration to calculate a distance between the fault and the unit;

determining the location of a fault on the wire using the calculated distance; and identifying components at the facility which have impaired performance.

2. The method according to claim 1 , wherein determining the location of a fault comprises correlating the time duration information with the components with impaired performance to determine the fault location.

3. The method according to claim 1 , wherein the unit communicates with external components via an Ethernet link.

4. The method according to claim 1 , wherein the underwater fluid extraction facility comprises a subsea hydrocarbon extraction facility.

5. The method according to claim 2 , wherein the unit communicates with external components via an Ethernet link.

6. The method according to claim 5 , wherein the underwater fluid extraction facility comprises a subsea hydrocarbon extraction facility.

7. An underwater fluid extraction facility comprising means for determining the location of a fault in a cable at the facility, the fault location determination means comprising a time domain reflectometry unit, the unit being connected to at least one wire within the cable, and means for identifying components at the facility which have impaired performance.

8. The facility according to claim 7 , wherein the fault location determination means comprises:

means for causing the unit to transmit a current pulse to the wire;

means for detecting a reflected pulse received at the unit;

means for determining the time duration between the pulse transmission and the reflected pulse reception and using the duration to calculate a distance between the fault and the unit; and

means for determining the location of a fault on the wire using the calculated distance.

9. The facility according to claim 7 , wherein the unit is located within a module selected from the group consisting of a communications electronic module, a subsea electronics module and a power and communication distribution module.

10. The facility according to claim 7 , wherein the unit comprises an Ethernet link for communication with external components.

11. The facility according to claim 7 , wherein the underwater fluid extraction facility comprises a subsea hydrocarbon extraction facility.

12. The facility according to claim 8 , wherein the unit is located within a module selected from the group consisting of a communications electronic module, a subsea electronics module and a power and communication distribution module.

13. The facility according to claim 8 , wherein the unit comprises an Ethernet link for communication with external components.

14. The facility according to claim 12 , wherein the unit comprises an Ethernet link for communication with external components.

15. The facility according to claim 8 , wherein the underwater fluid extraction facility comprises a subsea hydrocarbon extraction facility.

16. The facility according to claim 12 , wherein the underwater fluid extraction facility comprises a subsea hydrocarbon extraction facility.

17. The facility according to claim 13 , wherein the underwater fluid extraction facility comprises a subsea hydrocarbon extraction facility.