在样品测定过程中，突然表头指针回零，电源指示灯和光源灯熄灭，再次启动时无任何反应。1分析与检修打开机壳，仔细检查电路板上的元器件，没有明显的烧焦痕迹。但发现电源保险丝BL1熔断。更换1A保险管后通电，观察到电源指示灯闪亮的瞬间，BL1又烧断，可以断定电路中有严重的 During the measurement of the sample, the head of the meter is suddenly returned to zero, the power indicator and the light source lamp are extinguished, and nothing happens when the indicator is turned on again. 1 Analysis and Inspection Open the casing, carefully inspect the components on the circuit board, there is no obvious marks of burning. However, it was found that the power fuse BL1 was blown. Replace the 1A fuse after power, observe the flashing power indicator light, BL1 blown again, you can conclude that the circuit has serious