(1) Inspection of transformer power transmission before operation
Check whether all kinds of test documents are complete, whether the primary and secondary leads have the same phase and correct phase color as well as the connection situations of grounding wire. The transformer should be cleaned and covered with no debris. The body and the attached bodies of the transformer should have no defects and be oil free. The ventilation is completely installed, the work of which is normal with accident discharge facilities in good conditions and the fire-fighting facilities complete. The oil throttle of the oil-immersed transformer should be opened. The throttle instructions should be correct and the oil level be normal. The voltage switching position of the oil-immersed transformer is in normal voltage gear. The setting value of the protection device should meet the requirements, with the operation and linkage test normal.
(2) Operation of transformer power transmission
1. The transformer is to be examined by the impulse test . When the transformer is first put into the operation, full pressure, input from the high voltage side, can be used to hit the switch-on. The duration should be no less than 10 min, with no abnormal conditions occur.
2. We can judge the conditions of the transformer according to different sounds through the process of the impulse test. When the transformer is normal, there is a hum. But there are other sounds indicating the transformer is abnormal: If the sound is relatively large and uniform, the added voltage is probably too high; When the sound is loud and noisy, the core may be loose; If there is a creaking sound, flashover may occur in the core or the surface of the casing; If the sound is bursting, the breakdown of core may happened.