Laserfiche WebLink
SUPERCHARGER SAFETY MECHANISMS T = 5 L n <br /> Supercharger System Safety Mechanisms <br /> Switchgear Overcurrent Protection <br /> The switchgear on the Supercharger site contains a main breaker and branch circuit breakers for each Supercharger <br /> Cabinet. The main and/or branch breakers typically feature ground fault current interruption (GFCI)or residual current <br /> device (RCD) capability. <br /> Metal Oxide Varistor (MOV) for Overvoltage Protection <br /> The Supercharger Cabinet contains metal oxide varistors (MOV) upstream of the charger modules to protect the Cabinet <br /> against AC overvoltage. <br /> AC Branch Fuses <br /> The Supercharger Cabinet distributes 3-phase AC input to internal charger modules. The Cabinet contains fast-acting AC <br /> fuses on each phase upstream of each charger module, as well as within the charger modules themselves, to protect <br /> equipment from AC overcurrent. <br /> Ground Fault Current Interruption (GFCI) Detection <br /> To protect against weak shorts between the hot AC lines and ground, each charger module within the Cabinet contains <br /> ground fault current interruption (GFCI) mechanisms. The GFCI trips if current in the AC lines and neutral are not <br /> balanced to within a specified threshold. <br /> Floating DC Voltage <br /> Each charger module within the Cabinet contains an internal isolation transformer upstream of the rectification <br /> components, which allows the downstream DC voltage to be floating (both positive and negative polarities have high- <br /> impedance isolation from ground). This ensures that if any one polarity experiences a fault to ground, no grounded <br /> equipment will become energized. The Supercharger system also performs isolation monitoring before and during charge <br /> sessions (described later in this document) and shuts down the DC output within milliseconds in case of a fault. In the <br /> absence of AC power, switching power electronics are disabled and power cannot be transferred across the galvanic <br /> isolation barrier. <br /> L1 <br /> L2 <br /> B Supercharger Cabinet <br /> N DC+ <br /> Charge <br /> pE Post <br /> DC- <br /> Galvanic Isolation <br /> DC Fuses and Contactors <br /> The DC power flow is routed through trunk fuses in the Supercharger Cabinet to protect against both output overcurrent <br /> and reverse fault current. Internal contactors control the DC power connection and allocation of charging blocks between <br /> up to two Supercharger Charge Posts. <br /> Rev. 1.0, September 2018 CONFIDENTIAL INFORMATION-SHARED UNDER NDA ONLY Page 3 of 8 <br />