| 摘要 |
PURPOSE:To prevent the breakdown of a switching element, and to prevent the lighting failure of a fluorescent lamp. CONSTITUTION:Both ends of an output side of a step-down transformer 10 are connected to one end of a resistor 22 through diodes 20, 21, and the other end of the resistor 22 is connected to a minus terminal of a full wave rectifier circuit 6 through a resistor 23. A capacitor 24 is connected across the resistor 23, and a base of a transistor 26 is connected to a connection point of the resistors 22, 23 through a resistor 25. The anode of a diode 28 is connected to a plus terminal of the output side of the full wave rectifier circuit 6, and a collector of the transistor 26 is connected to a cathode thereof through a relay 27, and an emitter is connected to a minus terminal of the output side of the full wave rectifier circuit 6. With this structure, interruption of an inverter circuit by the surge of high frequency voltage of another operated inverter circuit through a fluorescent lamp is prevented. |
