The difference between isolation switches and circuit breakers

Isolation switches and circuit breakers are important equipment in the power system, but they have obvious differences. The following is a detailed explanation of the differences, precautions, and methods between isolation switches and circuit breakers:

1、 Function and purpose

Isolating Switch:

Mainly used for isolating circuits, so that a certain part of the circuit can be safely repaired or replaced without interrupting the power supply of the entire circuit.

It does not have an arc extinguishing device, so it cannot be used to carry current.

Usually, there are obvious visible breakpoints in the disconnected state, allowing maintenance personnel to clearly see which parts are disconnected.

Circuit Breaker:

Mainly used to protect circuits, when the current in the circuit exceeds the predetermined value, the circuit breaker will automatically disconnect the circuit to prevent faults caused by overload or short circuit.

It has an arc extinguishing device that can carry and disconnect current.

In addition to overload and short circuit protection, modern circuit breakers can also provide various other protection functions.

2、 Operation methods and precautions

Isolating Switch:

Usually manual operation is required, and clear disconnection points should be ensured during the operation process.

When performing switching operations, the status of the switch should be checked first to ensure that it is in the disconnected state.

Due to the absence of an arc extinguishing device, the isolation switch may generate an arc during the opening and closing process, so extra caution should be taken during operation.

Circuit Breaker:

Usually operated by electric means, it can be remotely controlled.

Before switching, check whether the current and voltage in the circuit are normal.

During the operation of the circuit breaker, there may be arcing, so it is necessary to ensure that the arc extinguishing device of the circuit breaker is intact and effective.

3、 Maintenance and upkeep

Isolating Switch:

Regular inspection of the mechanical and electrical performance of the switch is required.

Ensure that the operating mechanism of the switch is normal and free from jamming.

The contact part should be regularly cleaned and inspected to ensure good contact.

Circuit Breaker:

The mechanical and electrical performance of the circuit breaker should be regularly checked to ensure its normal operation.

Regularly inspect and maintain the arc extinguishing device to ensure it can operate normally when needed.

Regular cleaning and inspection are also required for the contact part.

4、 Usage and Tips

Isolating Switch:

When conducting circuit maintenance, the isolation switch should be disconnected first to ensure that the circuit is in a safe state.

When switching, it should be done slowly to avoid generating excessive arcs.

Circuit breaker:

Under normal working conditions, the circuit breaker should remain closed.

When an overload or short circuit fault occurs, the circuit breaker should automatically disconnect the circuit. At this time, the fault should be carefully checked and eliminated, and then the circuit breaker should be manually reset. If the circuit breaker cannot be closed due to a malfunction, it should be replaced in a timely manner.

For circuit breakers that require manual operation, the operating mechanism should be checked first to ensure that it is functioning properly before proceeding with the operation. During the operation, the operating handle should be slowly pushed to avoid excessive force causing arc formation.

In short, the roles of isolation switches and circuit breakers are very important in the power system. The correct use and maintenance of these two types of equipment are key to ensuring the safe and stable operation of the power system. During use, relevant operating procedures and precautions should be strictly followed to avoid safety accidents.