A study on DC limit parameters in RCD operation using capacitor

Abstract

Residual-current devices (RCDs) are used to protect humans from electrical shocks. This study explores the DC limit parameters of RCDs using the capacitor. To find out the possible parameters, a common signal from the RCD in AC waveform is analyzed using a digital oscilloscope for reference. This signal is then transformed into a DC signal using a common circuit of a full-bridge rectifier, capacitor, and a voltage regulator. Finally, the signal is characterized using an oscilloscope and multimeter. The result of this work is I-V characteristic of the DC measurement obtained from the RCD. It shows two possible parameters. First is a voltage gap of 1 V which representing input current with a range from 0.4 to 64.3 mA. Second is an increasing speed of 1.06 V/s on average. These parameters could be used to overcome the nuisance trips of common RCDs.