| 摘要 |
PURPOSE:To obtain a grounding point simply with high accuracy, by monitoring a grounding voltage and a power supply voltage detected with the power supply voltage and an assumed grounding system and detecting a grounding fault point with the power supply voltage and the grounding voltage at a grounding failure. CONSTITUTION:When no grounding exists in a load circuit and power supply is normally performed, an assumed grounding voltage is taken as (0) voltage and the voltage distribution is symmetrical to positive and negative polarity. If a grounding failure takes place on the way of a load, i.e., between resistors R1 and R2, a grounding voltage of -VE2 is generated. Thus, the voltage characteristics taking the assumed grounding point is taken as zero volt are lost and they become that the grounding point is taken as zero volt. Thus, the grounding voltage and power supply voltage detected with the power supply voltage and the assumed grounding system are monitored with a monitor circuit, the power supply voltage and the grounding voltage at failure are tied with a straight line and a cross point between the prolonged line and the zero line is obtained as the ground failure point. Thus, the grounding point can simply be obtained with high accuracy. |
