三极环形压敏电阻测试分选仪的研制

R & D of instruments for screening three-electrodering varistors

三极环形压敏电阻分选仪可对三极电压测试,并逐一和设定的上、下限电平比较,同时计算三极电压的差值并和设定的超差电平比较,然后将测试结果显示出来,整个过程用时小于0.5 s.测试结果分为合格、偏高、偏低和超差四类,测试精度为0.8％.和用普通压敏电阻测试仪人工分选的方式相比,其准确率提高5倍以上,劳动效率提高3倍以上.

A new instrument is made and used to screen the three - electrode ring varistor by measuring the individual voltages of the three electrodes, comparing them with the corresponding preset upper and low limits, calculating the resultant difference voltages for each of the three electrodes, and again comparing them with the preset difference values. The screening result, with a precision of 0.8 % , can be displayed within 0.5 second. The varistors are screened into four categories, namely accepted, higher than the preset difference voltage, lower than the preset difference voltage, and defected. By employing the new instrument, the measurement precision is increased by more than 5 times, and the productivity more than 3 times, as compared to those obtained by using the manual screening method with a traditional instrument.