Electrical injury protection system using radio frequency transmission

• US 6,897,783 B2
• Filed: 02/23/2001
• Issued: 05/24/2005
• Est. Priority Date: 03/03/2000
• Status: Expired due to Fees

• Current Assignee: The Government of United States of America As Represented By The Secretary of The Department of Health And Human Services, Centers For Disease Control And Prevention
• Original Assignee: United States Department Of Health And Human Services
• Inventors: Conover, David L., Zeng, Shengke, Jackson, Larry L., Powers, John R. Jr.
• Primary Examiner(s): Lieu, Julie Bichngoc
• Application Number:
  US10/204,031
• Publication Number:
  US 20030011484A1
• Time in Patent Office: 1,551 Days
• Field of Search: 340/635, 340/657, 340/660, 340/661, 340/573.1, 340/539.1, 340/539.11, 340/539.21, 340/573.4, 340/539.26, 340/636.1, 324/457
• US Class Current: 340/635
• CPC Class Codes: H02H 5/12 responsive to undesired approach to, or touching of, live parts by living beings

Abstract

A personal electrical injury protection system is provided which can be worn by electricians, construction workers, or other individuals working around or with low-voltage lines (i.e. generally less than about 600 volts). The personal electrical injury protection system has both a proximity warning component which provides a warning of potential electrical hazards upon close approach to the low-voltage power line and an electrical contact protection component which turns off the power upon actual electrical contact with the power line. The present personal electrical protection system relies on a radio frequency transmitter attached to the worker or person to be protected and a radio receiver/controller connected to the power line. The radio frequency transmitter has a low frequency generator which is used for electrical-contact protection and a high frequency generator which is used for proximity warning.

Claims

1. A personal electrical injury protection system for use by an individual working near a power line, the system comprising:

a radio frequency transmitter mounted on the individual'"'"'s body for generating a radio signal, at least two electrodes connecting the radio frequency transmitter to the individual'"'"'s body such that the body acts as an antenna for transmitting the radio signal, the radio signal carrying at least information relating to the individual'"'"'s proximity to the power line;

a controller electrically connected to the power line for receiving the radio signal, wherein the controller comprises an approach warning mechanism to monitor the radio signal for proximity information; and

an alarm operatively coupled to the controller wherein, if the approach warning mechanism detects that the radio signal is greater than a first threshold value, an approach warning signal is generated which is transmitted to the alarm and activates the alarm to warn the individual of a close approach to the power line.

2. The personal electrical injury protection system of claim 1 wherein the radio signal carries information relating to the individual'"'"'s electrical contact with the power line and the controller comprises a quick tripping mechanism to monitor the radio signal for electrical contact information wherein, if the quick tripping mechanism detects that the radio signal is greater than a second threshold value, the power line is de-energized to minimize electrical injury to the individual.

3. The personal electrical injury protection system of claim 1 wherein the radio signal is in the range from about 100 kHz to about 1 MHz.

4. The personal electrical injury protection system of claim 2 wherein the radio signal comprises a low frequency radio signal for carrying information relating to the individual'"'"'s electrical contact with the power line and a high frequency radio signal for carrying information relating to individual'"'"'s proximity to the power line and wherein the approach warning mechanism is operable to receive the high frequency radio signal and the quick tripping mechanism is operable to receive the low radio frequency signal.

5. The personal electrical injury protection system of claim 1 wherein the alarm is carried by and electrically coupled to the transmitter.

6. The personal electrical injury protection system of claim 1 wherein the alarm is electrically coupled to the approach warning mechanism.

7. The personal electrical injury protection system of claim 1, wherein the alarm is a variable pitch audible alarm which provides a higher pitch audio output the closer the individual approaches the power line.

8. The personal electrical injury protection system of claim 2 wherein the quick tripping mechanism de-energizes the power line by causing an artificial line-ground current to trip a ground fault circuit interrupter on the power line in the minimum tripping delay time of the ground fault circuit interrupter.

9. The personal electrical injury protection system of claim 2, wherein the quick tripping mechanism has a delay time of less than about 20 milliseconds to de-energize the power line.

10. The personal electrical injury protection system of claim 1, wherein the radio frequency transmitter is battery powered.

11. The personal electrical injury protection system of claim 1, wherein the radio frequency transmitter can be mounted on a belt, tool holster, helmet, or shoe or can fit into a shirt or other pocket.

12. The personal electrical injury protection system of claim 10, wherein the radio frequency transmitter can be mounted on a belt, tool holster, helmet, or shoe or can fit into a shirt or other pocket.

13. The personal electrical injury protection system of claim 10, wherein the radio frequency transmitter has a low-battery warning light or other alarm.

14. The personal electrical injury protection system of claim 12, wherein the radio frequency transmitter has a low-battery warning light or other alarm.

15. The personal electrical injury protection system of claim 4, wherein the high frequency radio signal is in the range of 200 kHz to about 2 MHz and the low frequency radio signal is in the range of about 50 kHz to about 200 kHz.

16. The personal electrical injury protection system of claim 1, wherein the controller is electrically connected to the power line through an outlet on the power line.

17. The personal electrical injury protection system of claim 2, wherein the quick tripping mechanism de-energizes the power line when electrical contact is detected by automatically causing an artificial line-neutral over-current to trip a circuit breaker on the power line.

18. The personal electrical injury protection system of claim 2, wherein the quick tripping mechanism de-energizes the power line when electrical contact is detected by automatically causing an artificial line-neutral over-current by controlling a silicon controlled rectifier connected to a low-resistant resistor between line and neutral of the power line.

19. The personal electrical injury protection system of claim 2, wherein the quick tripping mechanism de-energizes the power line when electrical contact is detected by automatically causing an artificial line-ground current to trip a ground fault circuit interrupter on the power line.

20. The personal electrical injury protection system of claim 2, wherein the quick tripping mechanism de-energizes the power line when electrical contact is detected by automatically causing an artificial line-ground current to trip a ground fault circuit interrupter on the power line by controlling a silicon controlled rectifier connected to a low-resistant resistor between line and ground of the power line.

21. A personal electrical injury protection system for use by an individual working near a low voltage power line, the system comprising:

(1) a radio frequency transmitter mounted on the individual'"'"'s body and having a low frequency signal generator for generating a low frequency signal, at least two electrodes connecting the radio frequency transmitter to the individual'"'"'s body, and an alarm; and

(2) a controller electrically connected to the power line for receiving the low frequency signal from the low frequency signal generator, wherein the controller has a quick tripping mechanism to monitor the low frequency signal from the low frequency signal generator;

wherein the low frequency signal carries information relating to the individual'"'"'s electrical contact with the power line, and

wherein, if the quick tripping mechanism detects that the low frequency signal is greater than a predetermined threshold, the power line is de-energized to minimize electrical injury to the individual.

22. The personal electrical injury protection system of claim 21, wherein the radio frequency transmitter and the low frequency signal generator are contained in a combined radio frequency transmitter and receiver unit which can be worn by the individual.

23. The personal electrical injury protection system of claim 21, wherein the quick tripping mechanism has a delay time of less than about 20 milliseconds to de-energize the power line.

24. The personal electrical injury protection system of claim 21, wherein the radio frequency transmitter is battery powered.

25. The personal electrical injury protection system of claim 24, wherein the radio frequency transmitter has a low-battery warning light or other alarm.

26. The personal electrical injury protection system of claim 24, wherein the radio frequency transmitter can be mounted on a belt, tool holster, helmet, or shoe or can fit into a shirt or other pocket.

27. A personal electrical injury protection system for use by an individual working near a power line, the system comprising:

a radio frequency transmitter mounted on the individual'"'"'s body for generating a radio signal, at least two electrodes connecting the radio frequency transmitter to the individual'"'"'s body such that the body acts as an antenna for transmitting the radio signal, the radio signal carrying at least information relating to the individual'"'"'s electrical contact with the power line; and

a controller electrically connected to the power line for receiving the radio signal, wherein the controller comprises a fast tripping mechanism to monitor the radio signal for electrical contact information and wherein the fast tripping mechanism causes an artificial line-neutral over current to trip a circuit breaker on the power line when the radio signal is greater than a threshold value.

29. The personal electrical injury protection system of claim 27, wherein:

the controller is operable to generate a radio signal carrying at least information relating to the individual'"'"'s proximity to the power line;

the radio frequency transmitter comprises an alarm and is operable to receive the signal from the controller, wherein the transmitter activates the alarm if the signal from the controller exceeds a predetermined value.

30. The personal electrical injury protection system of claim 29, wherein the signal generated by the controller is a high frequency signal, and the signal generated by the radio frequency transmitter is a low frequency signal.

31. The personal electrical injury protection system of claim 30, wherein the high frequency signal is in the range of about 200 KHz to about 2 MHz and the low frequency signal is in the range of about 50 kHz to about 200 kHz.

32. The personal electrical injury protection system of claim 27, wherein:

the controller is operable to generate a radio signal carrying at least information relating to the individual'"'"'s proximity to the power line; and

the radio frequency transmitter is operable to receive the signal from the controller, wherein the transmitter generates said signal carrying at least information relating to the individual'"'"'s electrical contact with the power line if the signal from the controller exceeds a predetermined value.

28. A personal electrical injury protection system for use by an individual working near a low voltage power line, the system comprising:

a radio frequency transmitter mounted on the individual'"'"'s body and having a low frequency signal generator for generating a low frequency radio signal, at least two electrodes connecting the radio frequency transmitter to the individual'"'"'s body such that the body acts as an antenna for transmitting the low frequency radio signal, a receiver, and an alarm; and

a controller electrically connected to the power line for receiving the low frequency radio signal from the radio frequency transmitter, the controller having a high frequency signal generator for generating and transmitting a high frequency radio signal, wherein the receiver of the radio frequency transmitter monitors the high frequency radio signal from the controller and the controller has a quick tripping mechanism to monitor the low frequency radio signal from the radio frequency transmitter;

wherein the high frequency radio signal carries information relating to the individual'"'"'s proximity to the power line and the low frequency radio signal carries information relating to the individual'"'"'s electrical contact with the power line,

wherein, if the the radio frequency transmitter detects that the high frequency radio signal is greater than a first threshold value, an approach warning signal is generated which is transmitted to the alarm and activates the alarm to warn the individual of a close approach to the power line, and

wherein, if the quick tripping mechanism detects that the low frequency radio signal is greater than a second threshold, the power line is de-energized to minimize electrical injury to the individual.

33. A personal electrical injury protection system for use by an individual working near a low voltage power line, the system comprising:

(1) a radio frequency transmitter mounted on the individual'"'"'s body and having a low frequency signal generator, a high frequency signal generator, at least two electrodes connecting the radio frequency transmitter to the individual'"'"'s body, and an alarm;

(2) a radio frequency receiver to pick up the low frequency radio signal and high frequency radio signal from the radio transmitter; and

(3) a controller electrically connected to the power line and electrically connected to the radio frequency receiver for receiving the low frequency signal and the high frequency signal from the radio frequency receiver, wherein the controller has an approach warning mechanism to monitor the high frequency signal from the receiver and a quick tripping mechanism to monitor the low frequency signal from the receiver;

wherein the high frequency signal carries information relating to the individual'"'"'s proximity to the power line and the low frequency signal carries information relating to the individual'"'"'s electrical contact with the power line,

wherein, if the approach warning mechanism detects that the high frequency signal is greater than a first threshold value, an approach warning signal is generated which is transmitted to the alarm and activates the alarm to warn the individual of a close approach to the power line, and

wherein, if the quick tripping mechanism detects that the low frequency signal is greater than a second threshold, the power line is de-energized to minimize electrical injury to the individual.