Computer animated digital arc diagnostic system

An arc diagnostic system has been developed for analyzing arc motion, structure, and intensity in electrical components such as molded case circuit breakers and contactors. The system utilizes an array of fiber-optic cables and matching photodiode receivers to monitor the light from an arc and convert the light into electrical signals, which are acquired by a high-speed transient digitizing system. The two unique aspects of this system are in the animation and arc intensity capabilities. Acquired images of the arc (up to one image per microsecond) are superimposed on a CAD drawing of the device being tested and reanimated frame by frame on a personal computer screen. Arc intensity is proportional to the spot size shown in the reanimation. The system can also acquire corresponding current, arc voltage, and arc chamber pressure, which are correlated to the reanimation. High-power short circuit tests were performed on a current limiting molded case circuit breaker (MCCB) to illustrate system capabilities. Discussions about the acquired results are presented, as well as future refinements to the system