| 摘要 |
PURPOSE:To detect the abnormal condition of an oil-filled electric equipment quickly and prevent the equipment from being damage, by a method wherein sampled oil is collected two times and more from a container having sampled oil at the specified depth immediately after churning the oil with a suction tube and after pacifying the oil for a certain period of time after the churning, and the distribution of dust in the oil is measured so as to compute the specific gravity of the dust contained therein. CONSTITUTION:In the method of judging whether the dust contained in oil-filled electric equipment is produced by carbon grains generated by internal abnormal conditions such as arc and corona discharge by measuring the specific gravity of the dust, sampled oil 12 is collected in a cylindrical container 10 in which the suction port of a suction tube 14 is put in the oil at the specified depth h from the liquid surface, while the oil 12 is being churned. When the viscosity of the oil is too high, it may be diluted with alcohol. Immediately after the oil is churned, it is collected partly by a suction device 16, using a filter 18 to remove matter with large grains. A part 20 is used to measure the logarithmic ratio of the diameter of the dust in the oil to its density and display the ratio. The oil is again collected and measured at a certain time after it has been pacified. The specific gravity of the dust grain is computed by the use of the specified operating expression from both the measured values. Thus abnormal conditions are quickly detected while the occurrence of serious accidents can be prevented. |
