The invention relates generally to diagnostics of wiring systems and more specifically, to diagnostics of aircraft wiring systems.
Insulation failure in wiring systems in aircraft industry is a critical safety concern since discharges from electrical wires may lead to on-board fires or other hazardous conditions. Hence, maintenance of the wiring system is an important factor in maintenance of the aircraft. However, wiring in a typical aircraft may extend in length up to several kilometers, hindering manual inspection for defects.
Some commonly used diagnostic systems include time domain reflectometry and frequency domain reflectometry. The techniques include a pulsed signal that may be applied to the wiring system. A reflected signal is analyzed for anomalies in the wiring. However, these techniques require the wires to be disconnected from a harness.
Insulation failure has been primarily attributed to aging of the wires leading to cracks in the insulation. Further, improper installation and handling may also lead to defects in insulation. Initial degradation in the insulation may start with microscopic cracks that result in small electrical discharges. The discharges may further carbonize the insulation leading to a full arc discharge. The small electrical discharges cannot be detected by the existing diagnostic systems. In order to resolve the issue, multiple sensors are added that may acquire electromagnetic signals due to the electrical discharges. However, addition of sensors to the wiring system increases weight of the aircraft leading to an increased maintenance time and cost.
Hence, there is a need for an improved diagnostic system for the aircraft wiring system that addresses the aforementioned issues, including continuous monitoring and diagnostics during the operation of the aircraft.
In accordance with an aspect of the invention, a wire diagnostic clamp including a clamp body configured to receive a plurality of electrical wires is provided. The wire diagnostic clamp includes a sensor disposed within the clamp body and being configured to detect a defect in the plurality of electrical wires. The wire diagnostic clamp further includes a mounting component configured to mount the wire diagnostic clamp to a substrate.
In accordance with another aspect of the invention, a system for detecting defects in electrical wiring is provided. The system includes a wire diagnostic clamp having a clamp body and being configured to receive a plurality of electrical wires. The system also includes a sensor disposed within the wire diagnostic clamp body and being configured to detect a defect in the multiple electrical wires. The system further includes a mounting component configured to mount the wire diagnostic clamp to a substrate and a connector configured to provide an electrical connection between the sensor and a data acquisition system.
In accordance with another aspect of the invention, a method for detecting defects in electrical wiring is provided. The method includes disposing a sensor within a clamp body of the wire diagnostic clamp and around the multiple electrical wires within the wire diagnostic clamp, providing an electrical connection between the sensor and a data acquisition system via a connector, and mounting the wire diagnostic clamp body to a substrate.
These and other features, aspects, and advantages of the present invention will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:
As discussed in detail below, embodiments of the invention include a clamping apparatus, a system and a method for detecting defects in electrical wiring. The term ‘defects’ as used herein, refers to electrical discharges in the electrical wiring due to reasons such as, but not limited to, a failure in insulation in the electrical wiring due to aging of the electrical wiring, improper installation, improper handling, and external factors such as temperature and humidity. The clamping apparatus may be used in conjunction with a passive detection technique of General Electric, namely, Smart Wire diagnostic systems (SWDS), to detect defects in the electrical wiring. Further details of the SWDS may be obtained in U.S. Pat. No. 6,930,610 B2.
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A bundle of electrical wires 14 are installed within the wire diagnostic clamp 10. In a particular embodiment, the sensor 40 is disposed around the bundle of electrical wires 14 within the clamp body 12. In a particular embodiment, the wire diagnostic clamp 10 also includes a rubber cushion 24 to avoid direct contact between the electrical wires 14 and the clamp body 12 that is metallic. The rubber cushion 24 loops around the bundle of electrical wires 14.
There are a large number of electrical wires 14 carrying electrical power and communication signals for efficient operation of an aircraft system. The entire electrical wiring installation is hidden behind a wire harness 68 in an aircraft frame. Multiple wire diagnostic clamps 10 may be employed to enable organizing wiring and to avoid cluttering of the electrical wires 14. In a particular embodiment, the wire diagnostic clamps 10 are installed at a space of about 6 to about 8 inches along a length of a bundle of the electrical wires 14. The wire diagnostic clamps are lightweight and may replace existing clamps that are used in wire harnesses eliminating additional load on the aircraft system.
The various embodiments of a clamping apparatus and a system for detecting defects in an electrical wiring system and a method for the same described above thus provide a way to achieve convenient, efficient and accurate detection of defects. These techniques and systems also allow for highly efficient aircraft systems due to improved electrical wiring fault detection.
Of course, it is to be understood that not necessarily all such objects or advantages described above may be achieved in accordance with any particular embodiment. Thus, for example, those skilled in the art will recognize that the systems and techniques described herein may be embodied or carried out in a manner that achieves or optimizes one advantage or group of advantages as taught herein without necessarily achieving other objects or advantages as may be taught or suggested herein.
Furthermore, the skilled artisan will recognize the interchangeability of various features from different embodiments. For example, the use of a BNC connector with respect to one embodiment can be adapted for use with an aluminum wire diagnostic clamp described with respect to another. Similarly, the various features described, as well as other known equivalents for each feature, can be mixed and matched by one of ordinary skill in this art to construct additional systems and techniques in accordance with principles of this disclosure.
While only certain features of the invention have been illustrated and described herein, many modifications and changes will occur to those skilled in the art. It is, therefore, to be understood that the appended claims are intended to cover all such modifications and changes as fall within the true spirit of the invention.
This invention was made with Government support under contract number N00421-05-D-0116 awarded by NAVAIR. The Government has certain rights in the invention.