| 摘要 |
PURPOSE:To prevent a fault by which a switch is damaged, and comes not to be operated by welding, etc., by executing turn-on/off of a power factor adjusting capacitor in a non-utility electric work, in accordance with a load. CONSTITUTION:In a non-utility electric work for receiving electric power by a high voltage, converting it to a low voltage by a transformer, and distributing it to a local electric apparatus, when a three-phase load current is varied, a secondary side current of a current transformer 7 is varied, in accordance with which a current relay 8 is operated, and through an auxiliary relay 9, and electromagnetic switch 5 is turned on/off. This current relay 8 turns on a contact, when the load current has become 70% of the total load current, and does not turn it off until said current falls to 25%. When said current has become below 25%, the contact is turned off. In this way, when the load current has become 70%, a capacitor 3 enters into a low voltage circuit of a transformer 1, and it is cut off, when a negative voltage power has become below 25%. Accordingly, an operation by which the capacitor enters at a point A, and it is cut off at a point B is executed automatically. |
