| 摘要 |
PROBLEM TO BE SOLVED: To reduce a voltage drop caused by the leakage current of a lightning arrester and eliminate the danger of electric shocks even if humans come into contact by connecting, in parallel with each end of a discharge registering circuit, a linear resistor having a resistance value such that the leakage current of the lightning arrester can be grounded. SOLUTION: If a leakage current flows from a lightning arrester, a current flows from the H to E terminals of a discharge-register case 1. Then the impedance of a first nonlinear resistor R1 is as high as tens to hundreds of KΩ. A linear high resister 4 has a neon tube 5 connected thereto and allows almost no current to pass through it. By selecting a linear medium resistor 2 at around 100Ω, the leakage current almost entirely flows through this resistance and its voltage drop can be determined. Should the resistor 2 be damaged, a voltage determined by the impedance of the resistor R1 is applied to the neon tube 5 to cause a discharge so as to enable this failure to be announced without affecting the counting action of a discharge registering circuit T.
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