chenliangmoto 发表于 2009-11-19 22:33:16

有谁知道Ghost电压不?

测小电压的时候把电压表设计成低输入阻抗就没有干扰,如果设计成高输入阻抗这个Ghost干扰电压就显现了,谁能解释一下呢?

marx 发表于 2009-11-20 00:01:46

Phantom voltage,分容性感性两种,容性的阻抗高,几百k,降低输入阻抗可以去除。感性的阻抗很低,一般靠考究的接线来去除,基本原则是避免地线环路,信号与地闭合面积最小。

chenliangmoto 发表于 2009-11-20 09:07:38

多谢了,关于容性Phantom voltage,老美有个详细的解释

This network is connected across the input terminals to provide low input impedance.Low input impedance is used to reduce any “ghost” voltage to very small levels, about 1 to 2 volts.

“Ghost” voltage means voltage that appears on a conductor that is not actually energized.This often occurs on spare conductors in a conduit or cable.The spare conductors are very close to the live conductors.The capacitance between the live and spare conductors causes the “ghost” voltage to appear when the measurement is made with a high impedance meter.A DMM with 10 MΩ input impedance is one example of a high impedance meter.

上面提到的Spare conductors 和live conductors该怎么翻译啊?
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