Arc detectors

Most circuit protection devices use either fuses or circuit breakers to protect wiring from overload conditions. However, in many fault conditions the current that is drawn is often less than that necessary to cause the fuse or circuit breaker to trip. Consequently, the arc may continue to burn causing fires, explosions, or heat damage to surrounding materials. Hendry Telephone Products has developed a unique circuit that will detect an arc and reliably discriminate between nonarc signals. It will ignore low energy arc events and operate in a high noise environment. It will detect an arc occurring at a considerable distance from the monitoring point. It does not depend on radiated energy for any of its detection and has very high isolation to crosstalk. Most common filters and bypass capacitors in common usage have little impact on the operation of the detector. It does not depend on detecting a ground fault. It has also been designed so that it may be implemented using low cost methods in volume usage, allowing incorporation as a general protection device in small branch circuits.