| 摘要 |
PURPOSE:To prevent breakage of a discharge lamp caused by overcurrent even if an electric power supply line from an alternating current power supply is connected falsely to the illuminating equipment side in a discharge lamp lighting device and an illuminating device provided with a pulse generating circuit arranged separately from a ballast. CONSTITUTION:Three-wire wiring is carried out between a ballast block A and an illuminating equipment B, and switch means (51 and 52) which are operated by using voltage outputted from two wires among the three output wires of the ballast block A and control an electric power supply to the pulse generating circuit 3 side from an alternating current power supply 1 outputted through the other two wires among the three output wires by switching on/off, are arranged on the illuminating equipment B side. Thereby, only when wiring is carried out correctly, the alternating current power supply is carried out to the pulse generating circuit 3, and a discharge lamp 4 is lit up, and when the two-wire electric power supply line of the alternating current power supply is wired falsely to the illuminating equipment B side without passing through the ballast block A, the alternating current power supply to the pulse generating circuit 3 is cut off. Thereby, breakage of the discharge lamp 4 caused by false wiring can be prevented. |
