| 摘要 |
PURPOSE:To improve the efficiency of maintenance work by judging that with which short circuit duration the time without a change of the voltage waveform coincide to detect the position of a disconnected lamp. CONSTITUTION:During the short time (t) from the generation of a disconnected in lamps L1-Ln, to the time that the secondary side of a transformer is shortened and during the time T that the short circuit of the secondary side of the transformer is cancelled, the output voltage waveform of an alternating power source 1 is changed, and this change of the output voltage waveform of the alternating power source 1 is detected by a disconnected core detecting unit 35. A disconnected core position judging unit 7 judges that which one of respective lamps L1-Ln is disconnected by judging that with which short circuit duration different per respective lamps the time after the detection of a waveform change until the resumption of detecting operation of a waveform change by the disconnected core detecting unit 35 coincide. The arranged position of a lamp of which core is disconnected can be thereby detected. |
