1.Monitor the instrument
Oil - immersed transformer control panel instruments, such as ammeter, voltmeter, power meter should meter reading every 1 ~ 2h, draw the daily load curve. When running under overload, should be every 0.5h meter reading once, the meter is not in the control room, each class at least twice recorded.
2.Monitor the transformer supply voltage
The variation of the supply voltage should be within 5% of the rated voltage. If the voltage is too long or too low, you should adjust the transformer tap changer, so that the secondary voltage tends to normal.
3.Measure the three-phase current
For transformers, the line current should not exceed 25% of the low side of the rated current, should be adjusted when the load per phase, as far as possible so that each phase load tends to balance.
4.Transformer oil operation
Check the height of the oil level and the oil-filled casing, there should be no oil leakage at the seal.