Mobile QR Code QR CODE : The Korean Institute of Power Electronics
Title Voltage-Power Area for Arc-safe Operation of Electric Contacts in Low Voltage DC systems
Authors Yong-Jung Kim ; Hyosung Kim
Page pp.249-254
ISSN 1229-2214
Keywords Low Voltage DC (LVDC) system; Wall Mount Switch; Socket-oulet & Plug; Electricity Access Area; DC Break Arc; Arc-safe operation area.
Abstract In AC power systems, the load current naturally reaches zero every half cycle, which results in a short-term spark that lasts less than a quarter cycle after the switch has been turned off or the plug has been removed from the socket. However, in DC power systems, the load current flows continuously without zero crossings, which causes the breaking arc to be prolonged and to develop easily into plasma, resulting in a high risk of arc accidents. Therefore, to ensure safety against breaking arcs in DC power systems, protective regulations must be established, and the physical properties of arc generation and extinction in DC power systems must be examined. This study aims to explore the experimental characteristics of breaking arcs in low-voltage DC systems that occur in normal brass electrodes, which are the main components of residential contact-type wall-mounted switches and socket-outlet plugs. This study analyzes the characteristics of breaking arcs between brass electrodes and presents a safe operation area for the arcs that is defined by the supply voltage and load power level. This study will enable nonexperts to use conventional brass electrode-based wall-mounted switches and socket-outlet plugs safely.