(1) Safe operation of capacitor

The capacitor shall operate at rated voltage. as

For the time being, it is not possible to operate within the range of 5% of the rated voltage; when it exceeds 1.1 times of the rated voltage, only short-term operation is allowed. However, the overvoltage of outgoing line for a long time should be eliminated.

The capacitor shall be operated at the rated current of three-phase balance. If it is not possible temporarily, it is not allowed to work for a long time under 1.3 times of the rated current to ensure the service life of the capacitor.

The ambient temperature of the capacitor bank shall not exceed 40 , the average temperature within 24 hours shall not exceed 30 ℃, and the average temperature within one year shall not exceed 20 ℃. The temperature of capacitor shell should not exceed 60 ℃. If the above phenomenon is found, artificial cooling shall be adopted, and the capacitor bank shall be disconnected from the network if necessary.

(2) Monitoring of capacitor parameters

1) Temperature monitoring. If there is no manufacturer’s specification, the temperature of capacitor shall be – 40 - 40 , and temperature indicating wax shall be pasted on the shell of capacitor. The causes of abnormal temperature rise of capacitor during operation include: high operating voltage (high dielectric loss); influence of harmonics (small capacitance reactance and large current); inrush current of closing (frequent switching); deterioration of heat dissipation conditions.

2) Voltage monitoring. It shall operate at rated voltage, and it is allowed to operate at 1.05 times of rated voltage, and it shall not exceed 4 hours at 1.1 times rated voltage.

3) Current monitoring. The three-phase current difference of capacitor bank shall not exceed ± 5%.

(3) Input and exit of capacitor

When the power factor is lower than 0.85 and the voltage is low, it should be put into operation; when the power factor is close to 1 and there is a leading trend, the voltage should be withdrawn when the voltage is high.

In case of one of the following faults, emergency exit shall be carried out: serious overheating or even melting of the connection point; flashover and discharge of porcelain bushing; expansion and deformation of shell; abnormal sound of capacitor bank or discharge device; smoke, fire or explosion of capacitor.


Post time: Oct-23-2020