Electromagnetic susceptibility of earth leakage circuit breakers and a countermeasure

Abstract

The electromagnetic susceptibility (EMS) is the sensitivity of a device to an incoming electromagnetic interference. It is especially very important for devices related to safety to operate normally under unexpected noise. This paper experimentally investigated the EMS of ten kinds of commercial earth leakage circuit breakers (Equipment under test: EUT). This EMS test was carried out in a 3-meter anechoic chamber with an EMS automation measuring equipment, vertical radiating (or horizontal) antenna, and electric filed probe, and etc. During the test, the EUT was monitored through a video camera to check whether any malfunctions occurred. As for the results, there were no malfunctions for the electric field strength and frequencies mentioned in the JIS standard. However, some of the EUT malfunctioned at several specific values not mentioned in the JIS standard. In addition, a countermeasure to prevent malfunction is also mentioned in this paper.