The capacitance in parallel between the fire wire and the zero line suppression is generally referred to as the x capacitor. As the capacitor connection location is also relatively key days, the same need to comply with the relevant safety standards. The X capacitor is also one of the safe capacitors. The capacitance value of the x capacitor allows the capacitance value of the Y capacitor to be large, but a safety resistor must be connected in parallel at both ends of the x capacitor to prevent the power cord from being unplugged Because of the charging and discharging process of the capacitor, the plug of the power cord is charged for a long time. Safety Standards Require that when the power cord of a working machine is unplugged, the live voltage (or ground potential) at both ends of the power cord plug must be less than 30% of the original rated operating voltage within two seconds.