POTENTIAL INDICATOR FOR HIGH VOLTAGE SWITCHGEAR

• US 3,744,045 A
• Filed: 12/24/1970
• Issued: 07/03/1973
• Est. Priority Date: 12/24/1970
• Status: Expired due to Term

• Current Assignee: John M. Kozlovic, Russell E. Frink
• Original Assignee: John M. Kozlovic, Russell E. Frink
• Inventors: Frink, Russell E., Kozlovic, John M.
• Primary Examiner(s): Caldwell, John W.
• Assistant Examiner(s): Myer, Daniel
• Application Number:
  US05/101,346
• Time in Patent Office: 922 Days
• Field of Search: 340/248R,248B,248C,380,252 315/153,227R,231 174/139 324/96,122,133
• US Class Current: 340/654
• CPC Class Codes: G01R 19/155 Indicating the presence of voltage

Abstract

A neon glow tube is mounted proximate to the high voltage conductors or bus bars of metalclad or metal enclosed switchgear. In the presence of high voltage on these conductors, the tube glows. A light sensing device detects the glow from the neon tube and either converts it to an electrical signal which is amplified through a suitable amplifying means and transmitted to a remote indicator or a fiber optics bundle carries the light from the glow tube to the remote indicator. In either case, a warning or indication is provid1d to operating personnel of the existence of high voltage within the metalclad or metal enclosed switchgear.

Claims

1. A voltage presence indicator comprising a gas discharge tube, said gas discharge tube being capable of producing light in the presence of an electric field created by an associated voltage without being directly connected to said source of voltage, a light conducting channel disposed adjacent to said gas discharge tube and extending to a location away from said gas discharge tube, said channel being capable of transmitting said light, said light transmitted by said channel being adapted to indicate the presence of said electric field at said location away from said gas discharge tube, an electrical conductor disposed adjacent to said gas discharge tube, and a region of common electrical potential disposed in the vicinity of and spaced from said conductor, any voltage difference applied between said conductor and said region of common potential creating said electric field, said gas discharge tube comprising a pair of terminals, one of said terminals being capacitively connected to said conductor, the other of said terminals being capacitively connected to said common region, said channel comprising a fiber optics bundle, said fiber optics bundle having a light receiving end and an indicating end, said light entering said fiber optics bundle at said receiving end and leaving it at said indicating end, a combination electrically conducting support piece-capacitor plate, electrically insulating material surrounding said electrical conductor, said combination support piece-capacitor plate being disposed adjacent the outer portion of said electrically insulating material, said combination support piececapacitor plate having electrically connected thereto said one terminal of said gas discharge tube which is capacitively connected to said conductor, said combination support piececapacitor plate enhancing the capacitive coupling between said one terminal and said conductor and also supporting said gas discharge tube thereon.

2. The combination as claimed in claim 1 wherein said outer portion of said electrically insulated material has a generally circular outer periphery, said combination support piece-capacitor plate comprises a cylindrical body surrounding a portion of said circular insulating material to further enhance the support and capacitance coupling characteristic of said combination support piece-capacitor plate.

3. A voltage presence indicator as claimed in claim 2 wherein a light actuated electron control means, an electronic gain means connected to said electron control means and an indicating means connected to said gain means are provided, said light from said indicating end actuating said electron control means to cause said electron control means to control electrons in said electronic gain means, said electronic gain means, in turn, actuating said indicating means to indicate the presence of said electric field and said voltage difference.

4. A voltage presence indicator as claimed in claim 3 wherein said electron control means comprises a photoelectric cell, and said indicating means comprises an indicating lamp.

5. A voltage presence indicator as claimed in claim 4, wherein said indicator is disposed inside metal enclosed switchgear, said region of common potential being at electrical ground potential.

6. A voltage presence indicator as claimed in claim 5 wherein said indicating lamp is located remotely with respect to said metalclad switchgear.

7. A voltage presence indicator as claimed in claim 4 wherein a dielectric light shielding means is disposed between said gas discharge tube and said photoelectric cell, said shielding means forming an enclosure capable of sustantially excluding external light from within said enclosure, said gas discharge tube, said fiber optics bundle, and said photoelectric cell being disposed within said enclosure.

8. A voltage presence indicator as claimed in claim 7, said indicator being disposed inside metal enclosed switchgear, said region being at ground potential.

9. A voltage presence indicator as claimed in claim 8, wherein said indicating lamp is located remotely with respect to said metalclad switchgear.

10. A voltage presence indicator as claimed in claim 2, said indicator being disposed inside metal enclosed switchgear, said region of common potential being at electric ground potential.

11. A voltage presence indicator as claimed in claim 10, wherein said indicating end is terminated remotely with respect to said metalclad switchgear.

12. A voltage presence indicator as claimed in claim 2, wherein a dielectric light shielding means is disposed adjacent said gas tube and said receiving end, said shielding means forming an enclosure capable of substantially excluding external light from within said enclosure, said gas discharge tube and said receiving end of said fiber optics bundle being mounted within said enclosure.

13. A voltage presence indicator as claimed in claim 12, said indicator being disposed inside metal enclosed switchgear, said common potential region being at ground electrical potential.

14. A voltage presence indicator as claimed in claim 13 wherein said indicating end is terminated remotely with respect to said switchgear.

15. A voltage presence indicator comprising a gas discharge tube being capable of producing light in the presence of an electric field, an electrical conductor disposed adjacent to said gas discharge tube, and a common point of electrical potential, said electric field being created when a voltage difference is applied between said conductor and said common point of electrical potential, said gas discharge tube being not directly electrically connected to said conductor, a light actuated electron control means disposed adjacent to said gas discharge tube, an electronic gain means connected to said electron control means and an indicating means connected to said gain means, said light from said gas discharge tube actuating said electron control means to thereby actuate said electronic gain means to energize said indicating means, said gas discharge tube comprising two terminals, one of said terminals being capacitively connected to said conductor, the other of said two terminals being capacitively connected to said common point, said electron control means comprising a photoelectric cell, a combination electrically conducting support piece-capacitor plate, electrically insulating material surrounding said electrical conductor, said combination support piece-capacitor plate being disposed adjacent the outer portion of said electrically insulating material, said combination support piece-capacitor plate having electrically connected thereto said one terminal of said gas discharge tube which is capacitvely connected to said conductor, said combination support piece-capacitor plate enhancing the capacitive coupling between said one terminal and said conductor and also supporting said gas discharge tube thereon.

16. The combination as claimed in claim 15 wherein said outer portion of said electrically insulating material has a generally circular outer periphery, said combination support piece-capacitor plate comprises a cylindrical body surrounding a portion of said circular insulating material to further enhance the support and capacitance coupling characteristic of said combination support piece-capacitor plate.

17. A voltage presence indicator as claimed in claim 16, wherein said indicator is disposed inside metal enclosed switchgear, said common point being at ground potential.

18. A voltage presence indicator as claimed in claim 17, wherein said indicating means comprises an indicating lamp located remotely with respect to said switchgear.

19. A voltage presence indicator as claimed in claim 16, wherein a dielectric light shielding means is provided, said shielding means forming an enclosure capable of substantially excluding external light from the interior of said enclosure, said gas discharge tube and said photocell being disposed within said enclosure.

20. A voltage presence indicator as claimed in claim 19, said indicator being disposed inside metal enclosed switchgear, said common point being a ground electrical potential.

21. A voltage presence indicator as claimed in claim 20, wherein said indicator means comprises an indicating lamp is located remotely with respect to said metalclad switchgear.