1.The capacitor can not have oil leakage, oil seepage phenomenon.

2.The capacitor can not have oil dirt, dust.

3.The three-phase current should be basically balanced during operation, such as serious imbalance, indicating that the branch fuse is burned, and the corresponding fuse should be replaced in time.

4.The three-phase voltage should be close to the rated value, such as the voltage exceeds the capacitor's own rated voltage (400V) 1.1 times (440V), the electric starting should be withdrawn. The reasons are as follows:

① The capacitor's own heat loss (that is, the dielectric loss) is proportional to the quadratic of the voltage, the voltage increases by 10%, the heat loss increases by 21%, and the capacitor is easy to bulge, even rupture, explosion.

②Whether the capacitor needs to be cast back and the amount of cast back is determined by the power factor of the whole plant and the size of the load. In operation, the power factor should be maintained above 0.9 (referring to the low-voltage side of the charge).

③ For the monthly average power factor of the whole plant, the low-voltage charging should be above 0.9, and the high-voltage charging should be above 0.95, otherwise the fine. The electrician on duty at the end of each month knows what the average power factor of the whole plant is for the month.

④ At noon, evening, and night non-production time, the capacitor should be withdrawn in accordance with it, otherwise it will cause over-compensation, which will unnecessarily increase the transformer current, lead to a rise in voltage, and increase the copper loss of the transformer.

⑤ The capacitor discharge point resistance is reliable, can not be broken, to ensure that the capacitor is automatically discharged after the return, otherwise the capacitor remains a blue charge, the next closing is easy to produce a large current impact, burn the fuse.

After the power failure, the capacitor should automatically exit, otherwise it is easy to produce current impact when the next call comes.