| 摘要 |
PURPOSE:To prevent influence from being exerted upon starting of the other lamp even if abnormality is caused in one lamp by constituting a single set of lamp circuit while using starters constituted so that generated starting pulses do not return to the stabilizer side with every lamp, and connecting it to the stabilizer. CONSTITUTION:When electric power supply is inputted, and when respective lamps of high pressure sodium lamps 2 and 4 are all normal, starters 3 and 5 generate pulses, and only an easily lighted lamp is lighted among the lamps 2 and 4, and the starter of an unlighted lamp stops to generate the pulses. When an instantaneous electric power failure is caused, the unlighted lamp until then is lighted after the electric power supply is restored. For example, when a failure of emission tube leakage and so on are caused in the lamp 2, even if the pulses generated by the starter 3 due to electric discharge inside external bulb are absorbed, since a superimposed pulse type device is used as a starter, the pulses of the starter 5 are not absorbed in a lamp circuit of the lamp 2, so that the lamp 4 can be started normally. |
