该机高压供电是1.8千伏,高压指示电路如图1所示。一旦空气湿度超过60％以上时,该机开机常发生高压表指针超过额定指示值,甚至打坏表头。一直要等到开机加热10多分钟后,高压才指到正常值。故障分析:高压指示是由11R_1∥11R_411R_1∥11R_6和11R_3串联在A点取得17.8V分压的。由于分压上电阻是4只1MΩ大阻值电阻,一旦空气湿度较大就会在电阻表面上结露,对于高阻值电阻来说等效为并上了1个漏电阻R_N(图1的虚线所示),从而提高了 The machine high-voltage power supply is 1.8 kV, high-voltage circuit shown in Figure 1. Once the air humidity exceeds 60% or more, the machine often occurs when the indicator turns high pressure gauge over the rated value, or even damage the header. Wait until the boot more than 10 minutes until the high pressure refers to the normal value. Failure Analysis: High pressure indication is made by the 11R_1 // 11R_411R_1 // 11R_6 and 11R_3 in series at 17.8V partial pressure. As the partial pressure on the resistance of 4 1MΩ large resistance resistor, once the air humidity will be dew condensation on the resistance surface, equivalent to the high resistance value and on a leakage resistance R_N (Figure 1 Shown by the dotted line), thereby improving