Maintenance and maintenance of DC circuit breakers

In order to keep the main circuit breaker in good working condition, maintenance management must be strengthened.

1. Keep the air moist or dirty, and the pipes are not clean, which may cause the following consequences:

(1) The moist gas decomposes into mixed gases such as hydrogen and oxygen under the action of the arc, which destroys the insulation between the fractures after the main contact is broken. It is difficult for the arc or the arc to reignite, and it will cause the arc extinguishing chamber to burst in severe cases.

(2) Reduce the insulation strength of the supporting porcelain bottle and the cavity of the arc extinguishing chamber, causing creeping discharge.

(3) Foreign matter such as paint, rust and slag in the pipeline may block the air port, causing the main circuit breaker to malfunction and cause jamming.

(4) If foreign matter enters the arc extinguishing chamber, it may cause poor contact of the main contact, which will cause the non-linear resistor to burn due to long-term energization. In severe cases, it will cause the non-linear resistor porcelain bottle to burst.

Therefore, an oil-water separator is installed on the intake pipe of the air storage cylinder of the main circuit breaker, and there is a water drain valve at the lower part. The water should be drained regularly during maintenance to keep the air circuit clean.

2. Regular replacement of rubber parts

The main circuit breaker is a kind of pneumatic and electrical equipment with complex structure. Each component has high requirements on sealing performance. In order to ensure good sealing performance, rubber parts should be replaced regularly.

3. Regularly check the main components