| 摘要 |
PURPOSE:To reduce the degree of complicated control and to attain high reliability and high accuracy for a constant current supply device, by applying the control addition current to said current supply device via a current control addition circuit and an additional winding connected in series. CONSTITUTION:Constant current inverters 1i-1n are provided together with current detectors CES1-3 and control circuits 31-33. A switch SW1 is turned off in a constant current feed mode to avoid application of a control addition current Ialpha to an additional winding. Thus a feed output current I0 is outputted based on a reference current IS at the side of the circuit 31-33. When a fault location of a cable is oriented, a variable resistor RV within a circuit 6 is controlled to output a prescribed current. Then the switch SW1 is turned off to apply the current Ialpha to the addition winding. An optional output current I0 for orientation is obtained by giving various types of control to the resistor RV. |
