WRE-630 WRE-631 WRE-632 WRE-633 WRE-623 assembly thermocouple, after the 380V AC power is rectified, the electrolytic capacitor is charged through the charging chip resistor. When the charging power reaches a certain value (such as DC200V), the auxiliary power supply starts to supply power to the control board, so that the control board tasks so that the relay or thyristor is turned on, and the charging resistor no longer works. At startup, the smaller the charging resistance, the greater the current flowing through the rectifier bridge. Frequent novice inverter repairers call for a call and change the charging resistor. As soon as the inverter is turned on, the rectifier bridge is blown up immediately. Is the charging resistor selection too small? The answer is no.