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故障现象:一台OKI5330SC票据打印机每次开机都烧交流保险丝。 故障分析及排除:根据上述故障现象可知,打印机电源电路中存在严重短路。小心拆开机壳,拔掉所有连线,取出上面的机械部分,仔细观察该打印机的电源部分,除交流保险烧断外,并没有发现任何明显烧焦的痕迹。根据该打印机电源电路的原理可知:引起上述短路故障的原因不外乎以下三个方面:1)整流、滤波电路中有被损坏短路的元件;2)电源开关管B1420被击穿短路;3)起过流过压保护作用的单向可控硅D2
Symptom: An OKI5330SC bill printer every time it is burning AC fuses. Failure Analysis and Troubleshooting: According to the above symptoms we can see that there is a serious short circuit in the printer power circuit. Carefully open the case, unplug all the connections, remove the mechanical part above, carefully observe the power part of the printer, in addition to the exchange of insurance blow, and did not find any obvious signs of burning. According to the principle of the power supply circuit of the printer, it can be known that the cause of the above short circuit fault is nothing more than the following three aspects: 1) The components in the rectifying and filtering circuit are damaged and short-circuited; 2) The power switch tube B1420 is punctured and short-circuited; 3) Have played through the pressure protection of the one-way silicon D2