Guarding implies the use of an added low impedance conductor, maintained at the same potential as the high impedance circuit, which will intercept any interfering voltage or current.

而保护意味着使用保持在与高阻抗电路相同电位的附加的低阻抗导体来阻止可能的干扰电压或电流。

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Randal Gilbert from NIE said interfering with high voltage electricity could be lethal.

BBC: Vandalised substation

There is live high voltage equipment inside, and interfering with it can be unforgiving.

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