Development of appliance coupler for LVDC in information communication technology (ICT) equipment with having a protection of inrush current and arc

In direct current (DC) system, there is no zero-cross of voltage curve, so that dangerous arc discharge shall be occurred inevitably between poles. Also, inrush current must be occurred in capacitors inside of ICT equipment. These unpreferable phenomenons will be happened at every movement of connect and disconnect. So, stable protection shall be necessary for human safety. New appliance coupler with safety functions to avoid damages of both inrush current and arc discharge has been developed and this paper explains its developed mechanism and reports the significant result of verification tests. There has never been industrial standard for appliance coupler of LVDC yet. Even in IEC, this is still on discussions. So, verification tests in this paper were performed compliant to IEC TS 62735-2 which was already published and specifies Plug and Socket-outlet of 400 Vdc for data centers.