摘要
介绍了美国Culter-Hammer公司的IQ200电力参数计量表的功能特点。为便于分析,对易发生故障的电源部分据实物电路板测绘出了电路原理图。对在实际运行中的电源板无输出的故障给出了分析,结论是PWM(脉冲宽度调制)控制器UC3845的电源端的电解电容器容量衰减及电容耗散因数变大是导致UC3845欠压锁定的原因。
The function and character of electrical monitoring meter IQ200 are introduced. For analyzing the theory, the schematic circuit diagram of the power circuit is provided by measuring the devices of PCB. The failure which occurred in course of work is analyzed. The conclusion is that the electrolytic capacitor which parallel connected the power terminal of the PWM controller UC3845 result in the UC3845 under voltage lockout. Capacity of the capacitor is attenuated and the dissipation factor of the capacitor is increased.
出处
《现代电子技术》
2007年第22期180-182,共3页
Modern Electronics Technique
