Precautions for maintenance and replacement of chip capacitors

SMD capacitors are widely used because of their superior performance. It is usually used in high-stability oscillating circuits as loops, bypass capacitors and pad capacitors. What should I pay attention to in daily maintenance and replacement of chip capacitors? Let's take a look with Ping Shang Xiaobian.

Pay attention to the following points when repairing chip capacitors:

1) Due to the limitation of vacuum purification conditions, internal maintenance of chip capacitors is not allowed on site.

2) When it is found that the chip capacitor has serious appearance defects, overheating and insulation aging defects, it should be taken out of operation and replaced with a spare capacitor.

3) Cleaning once a quarter (usually performed during regular power outage inspections), mainly cleaning the capacitor frame and porcelain insulation, the discharge device of the capacitor bank, the ventilation device and vents of the capacitor room, and the electrical energy on the capacitor circuit.

When the chip capacitor bank needs to be replaced when a serious accident occurs,

1) Manually discharge the entire group of chip capacitors;

2) Discharge each SMD capacitor one by one, that is, use the metal ground rod installed on the insulating rod to contact the capacitor outlet terminal to discharge;

3) Carry out an inspection and replace any SMD capacitors with serious defects. (When replacing, you must check whether the capacitance value and insulation resistance are qualified according to the record data of the spare capacitor in advance, and check whether there is any leakage or oil leakage)

4) After replacing the qualified capacitors, try to energize it three times under the rated voltage. If there is no fault, retry the operation for 24 hours. During the trial operation, inspections and inspections should be strengthened.