ARC DETECTION CIRCUIT BY CONTACT FAILURE

摘要

The present invention is to provide a circuit for detecting arc due to contact failure, capable of detecting arc current up to arc current below 10 milliamperes by detecting arc voltage when arc is generated by contact failure, capable of detecting arc voltage due to contact failure using a distribution capacity to ground, and capable of detecting arc voltage when arc is continuously generated over a predetermined time. According to an embodiment of the present invention, a circuit for detecting arc due to contact failure is a circuit for detecting arc generated by contact failure between lines by being arranged at a back end part of an earth leakage breaker for in-house wiring, and comprises: a rectifying unit to rectify arc pulse current by contact failure; an arc voltage detection unit to detect arc voltage by the arc pulse current passing through the rectifying unit; a high-frequency pass filter combined with a front end or a back end of the arc voltage detection unit; a control signal generation unit to generate a relay driving control signal using the arc voltage detected by the arc voltage detection unit; and a relay to electrically connect a power line to a ground line in the in-house wiring by being controlled by the relay driving control signal. The control signal generation unit includes: a pulse signal generation unit to generate a predetermined pulse width by receiving the arc voltage via an input terminal; a pulse delay signal generation unit to generate a pulse delay signal when the pulse signal outputted from the pulse signal generation unit is higher than or equal to a predetermined number; and a driving control signal generation unit to generate a relay driving control signal to operate the relay using the pulse delay signal.