| 摘要 |
PROBLEM TO BE SOLVED: To accurately measure an insulation resistance value of a measurement object, as retaining electric discharge resistance.SOLUTION: Resistance values R, Rand Rof electric current limit resistance 14, a voltage division unit 15 and electric discharge resistance 16 are defined so as to satisfy an expression (a). A processing unit 20 is configured to execute: first measurement processing of connecting other end of the electric discharge resistance 16 to an internal ground G to measure an electric current value Ioff of an electric current I, and measuring a voltage value Voff of a first measurement terminal 11 on the basis of a division voltage Vdi; second measurement processing of connecting a negative side output terminal 13b to the internal ground G to generate an inspection DC voltage Vm, measuring an electric current value Ion of the electric current I, and measuring a voltage value Von to be applied to a voltage division unit 15 on the basis of the division voltage Vdi; and resistance calculation processing of calculating an insulation resistance value Rof a sunlight power generation unit 2 from the expression (b). R//(R+R)=R..(a) R=(Von-Voff-Ion*R)/(Ion-Ioff)..(b)SELECTED DRAWING: Figure 1 |
