Susceptibility of Relay Module to Conducted EMI

To investigate the response patterns of the relay module to conducted electromagnetic interference (EMI), a conductive susceptibility experiment was carried out using direct injection method (DPI). With single-frequency continuous wave interference injection, the frequency-domain response of the ‘on-off’ transition threshold of the relay module is measured. With the Pulse-Modulated (PM) signals injection, the results show that the relay module displays similar frequency-domain susceptibility responses for duty cycles surpassing 20%, yet inducing malfunctions in the relay becomes difficult for duty cycles below 20%. The susceptibility behavior of the relay module to interference signals varies with different frequencies. This variation is significant for analyzing the electromagnetic susceptibility of control circuits that use relays as their core components.