Method and apparatus for determining electrical contact wear

• US 7,038,201 B2
• Filed: 07/22/2004
• Issued: 05/02/2006
• Est. Priority Date: 12/13/2002
• Status: Expired due to Fees

• Current Assignee: Nichols Applied Technology LLC
• Original Assignee: Nichols Applied Technology LLC
• Inventors: Nichols, Bruce W.
• Primary Examiner(s): Wells, Nikita
• Assistant Examiner(s): Vanore, David A.
• Application Number:
  US10/896,689
• Publication Number:
  US 20040256551A1
• Time in Patent Office: 649 Days
• Field of Search: 250/259, 250/260, 250/302, 250/461.1, 250/484.2, 250/295
• US Class Current: 250/302
• CPC Class Codes: G01N 21/8422 Investigating thin films, e.g. matrix isolation method
• CPC Class Codes: H01H 1/0015 Means for testing or for inspecting contacts, e.g. wear indicator measuring circuits G01R31/3274
• CPC Class Codes: H01H 2001/0026 wherein one or both contacts contain embedded contact wear signal material, e.g. radioactive material being released as soon as the contact wear reaches the embedded layer
• CPC Class Codes: H01H 2001/0031 by analysing radiation emitted by arc or trace material

Abstract

A fluorescent trace material is provided within at least a portion of an electrical contact or interrupter assembly component, or a cavity defined therein. At least a portion of the fluorescent trace material is exposed or released from the electrical contact or interrupter assembly component, indicating a degree of component wear.

Claims

1. A method for determining erosion of a contact assembly, the method comprising:

providing a fluorescent trace material within the contact assembly;

allowing the contact assembly to be eroded until at least a portion of the fluorescent trace material is released into a surrounding medium; and

monitoring at least one point in the surrounding medium to detect a quantity of fluorescent trace material dispersed into the surrounding medium as an indicator of erosion of the contact assembly.

2. The method of claim 1, wherein the fluorescent trace material is provided within a cavity defined in the contact assembly.

3. The method of claim 1, wherein the monitoring step further comprises the steps of:

directing electromagnetic radiation into the surrounding medium; and

sensing the amount of radiation emitted by the fluorescent trace material to determine the amount of fluorescent trace material in the surrounding medium.

4. The method of claim 3, wherein the electromagnetic radiation is ultraviolet radiation.

5. The method of claim 3, wherein the electromagnetic radiation has a wave-length of about 254 nm.

6. The method of claim 4, wherein the ultraviolet radiation is generated from a source located within an enclosure surrounding the electrical contact assembly.

7. The method of claim 6, wherein the ultraviolet radiation is generated from a source located in a fluorescent trace material detecting device.

8. The method of claim 1, wherein the step of monitoring the surrounding medium comprises the steps of:

circulating the surrounding medium through a particulate concentration device;

directing electromagnetic radiation onto the fluorescent trace material in the particulate concentration device; and

detecting the level of fluorescent radiation emitted in response to the electromagnetic radiation.

9. The method of claim 8, wherein:

the particulate concentration device comprises a transparent or translucent observation wall; and

the electromagnetic radiation is directed through the observation wall to the fluorescent trace material.

10. A method for determining the presence of fluorescent material associated with wear of an electrical contact assembly, comprising the steps of:

generating electromagnetic radiation;

directing the electromagnetic radiation to fluorescent material indicating wear of the contact assembly;

detecting the amount of fluorescent radiation generated by the fluorescent material in response to the electromagnetic radiation; and

determining a level of wear of the electrical contact assembly from the amount of fluorescent radiation detected.

11. A method for determining the level of a fluorescent trace material present in a medium surrounding an electrical contact assembly, comprising the steps of:

circulating the surrounding medium through a particulate concentration device containing a collection surface;

directing electromagnetic radiation to the particulate concentration device; and

detecting the amount of fluorescent radiation generated by the fluorescent trace material collected by the particulate concentration device in response to the electromagnetic radiation.