Opto-electronic camera for noninvasive investigation of arcing in short-circuit current-carrying conductors and HRC fuse elements

The emergence of fast opto-electronic pixel-array chip technology enables development of optical systems for investigating arc ignition and arc extension in HRC fuses. A black-box slit-aperture camera design, based on such a sensor, is presented together with relevant data capture techniques and test procedures. Good data crosscorrelation of the camera-light-source attributes with circuit temporal and spatial arc-disposition attributes were achieved and evaluated. The camera is able to operate at approximately 15 000 frame/s in single-light-beam mode and at a maximum of 30 000 frame/s in two-beam mode. The results from the presented high-rupturing-capacity (HRC) fuse wire and element test procedures demonstrate good acuity of individual arc ignition data capture and multiple delayed arc capture. The results also demonstrate that the camera is able to distinguish the intensity, position and dimensions and correlate the attributes of extant fulgurites for arc ignitions occurring within 5 μs and for multiple arcs extending beyond 5 ms.