Detector for Detecting a Current Carrying Conductor and a Method of Validating Operation of the Detector

• US 20100060285A1
• Filed: 03/02/2009
• Published: 03/11/2010
• Est. Priority Date: 02/29/2008
• Status: Active Grant

• Current Assignee: Radiodetection Limited
• Original Assignee: Radiodetection Limited
• Inventors: Conway, Kevin, Pearson, Richard David
• Granted Patent: US 8,115,489 B2
• Time in Patent Office: Days
• US Class Current: 324/326
• CPC Class Codes: G01V 3/081 the magnetic field is produced by the objects or geological structures characterised by the method of magnetic field measurement G01R33/00

Abstract

A detector for detecting a buried conductor comprises a plurality of antennas B, T. Each antenna B, T has a winding wound around the antenna, the winding being connected to a current source for providing a predefined current in the winding. When the predefined current is applied to the winding an electromagnetic field is generated at the antenna which induces a test current in the antenna. The test current is compared to calibration data stored in the detector to validate the correct operation of the detector.

Claims

1. A detector for detecting a buried conductor, the detector comprising:

a plurality of antennas for detecting an electromagnetic field;

a plurality of windings, each wound around a respective antenna, each winding being connected to a current source for providing a predefined current in the winding to generate an electromagnetic field at the antenna, thereby inducing a test current in the antenna;

a memory for storing calibration data of the antennas; and

a processor configured to process the test currents in the antennas to determine if the test currents are within predetermined limits of the calibration data.

2. A detector as claimed in claim 1, wherein the predetermined limits for each antenna are the calibration data ±

0.01%.

3. A detector as claimed in claim 1, wherein the processor is configured to disable the detector if one of the test currents is outside the predetermined limits of the calibration data.

4. A detector as claimed in claim 1, wherein the plurality of antennas comprise two parallel antennas which in use are oriented horizontally and spaced vertically.

5. A detector as claimed in claim 1, wherein the plurality of antennas comprise three parallel antennas which in use are oriented horizontally and spaced vertically.

6. A detector as claimed in claim 1, wherein the processor is configured to store results of the test in the memory.

7. A detector as claimed in claim 1, further comprising a user interface for conveying the results of the test to a user.

8. A detector as claimed in claim 1, further comprising a communications module for transmitting results of the test to another device.

9. A system for validating the operation of a detector for detecting a buried conductor as claimed in claim 8, the system comprising:

a microprocessor-controlled device having a communications module for communicating with the communications module of said detector and a communications module for accessing a network, wherein the device is configured to receive test results from said detector and transmit the test results to said network.

10. A system as claimed in claim 9, further comprising a server connected to said network, wherein the server is configured to receive test results from the microprocessor-controlled device.

11. A system as claimed in claim 10, wherein the server is configured to generate a calibration certificate if the test results indicate that said detector is operating within predetermined limits.

12. A system as claimed in claim 11, wherein the calibration certificate is downloadable from the server to the microprocessor-controlled device.

13. A method of validating the operation of a detector for detecting a buried conductor as defined claim 1, the method comprising:

providing a predefined current in the winding to generate an electromagnetic field at each antenna, thereby inducing a test current in each antenna; and

processing the test currents to determine if the test currents are within predetermined limits of the calibration data.

14. A method as claimed in claim 13, wherein the predetermined limits for each antenna are the calibration data ±

0.01%.

15. A method as claimed in claim 13, wherein the processor disables the detector if one of the test currents is outside the predetermined limits of the calibration data.

16. A method as claimed in claim 13, wherein the plurality of antennas comprise two parallel antennas which in use are oriented horizontally and spaced vertically.

17. A method as claimed in claim 13, wherein the processor stores results of the test in the memory.

18. A method as claimed in claim 13, wherein results of the test are conveyed to a user via a user interface.

19. A method as claimed in claim 13, further comprising:

providing the detector with a communications module;

providing a microprocessor-controlled device having a communications module for communicating with the communications module of the detector; and

transmitting the results of the test from the detector to the microprocessor-controlled device via the communications modules.

20. A method as claimed in claim 19, further comprising:

providing the microprocessor-controlled device with a communications module for accessing a network; and

transmitting results of the test from the microprocessor-controlled device to said network.

21. A method as claimed in claim 20, further comprising:

providing a server connected to said network; and

transmitting results of the test from the microprocessor-controlled device to the server over said network.

22. A method as claimed in claim 21, further comprising:

generating a calibration certificate at the server if the test results indicate that the detector is operating within predetermined limits.

23. A method as claimed in claim 22, further comprising:

downloading the calibration certificate from the server to the microprocessor-controlled device.

24. A system for detecting a buried conductor, comprising:

a transmitter for generating an alternating current test signal in said conductor; and

a detector as claimed in claim 1 for detecting the signal generated in said buried conductor by the transmitter.