1.Switching power supply load short circuit fault, especially DC/DC converter short circuit or poor performance.
2.Output voltage end filter capacitor or rectifier diode failure
3.The performance of the switch decreases, leading to the failure of the switch tube to turn on, resulting in an increase in the internal resistance of the power supply and a decrease in the load capacity.
4.Undesirable switching transformer
5.Poor 300V filter capacitor