| 摘要 |
PURPOSE:To locate a short-circuited spot easily by generating flicker current by putting a variable resistor and a fixed resistor connected in series in one line of electric power source lines in series and increasing or decreasing the resistance value of the variable resistor. CONSTITUTION:One line L1 of electric power source lines L1, L2 is taken out of a breaker 2 and during the time, resistors R1, R2 are installed in the line L1. The resistance of the resistor R2 is so set as to make current at some amperes run in the electric power source line. More flicker current runs in the breaker line than in a short-circuited spot 3 by driving a movable contact piece 1 of the resistor R1 and no current runs to the terminal side further from the short-circuited spot 3. The flicker current running in the lines L1, L2 can be detected by a clamp meter and at that time the measured value of clamp meter deflects from the primarily set value as a mean value and thus the circuit can be distinguished from other circuits. Consequently, flicker current running in the electric power source line from the breaker is successively detected and short-circuit is detected by the fact that no flicker current passes the short- circuited plot 3 and no current is detected. |
