Circuit breaker and isolator are the electrical devices used in network stations and power plants to switch lines off or on. Electricity is very important in our life and we cannot imagine ourselves without it. But it can be detrimental in case of any breakdown that could damage the equipment or harm us. Circuit Breakers and Isolators are basically the devices that are installed in the system to prevent our lives and equipment in the event of a failure. The circuit breaker is automatically operated by a relay or electromechanical mechanism, while the isolator is manually operated. The circuit breaker is a loaded device while on the other hand the isolator is a loaded device. It means that the circuit breaker operates when the line is energized and any fault occurs.
What is circuit breaker?
Circuit breakers are available in many different sizes, dimensions and measurements, from small devices protecting a single piece of household equipment to huge switchgear made to protect high-voltage circuits serving an entire city. All circuit breakers currently have typical characteristics within their operation. Despite the fact that the details differ considerably regarding voltage class, current rating and circuit breaker type. The circuit breaker must identify a problem and a fault condition; on reduced voltage circuit breakers this is normally completed within the circuit breaker box. Circuit breakers with respect to massive currents or higher voltages are often arranged with shield relay pilot equipment to perfectly detect a fault condition and also for the particular trip opening feature to work. The particular trip solenoid that produces a latch is usually powered by a separate battery, although some high-voltage circuit breakers are usually self-contained along with current transformers, protective relays, and an internal management power supply. When the circuit breaker detects a fault, the circuit breaker contacts operate to break the connection of the fault area with the circuit and break the circuit; Various mechanically stored energies included within the circuit breaker are used to split the particular connections, however some of the necessary energy could be drawn from the fault current itself. Small circuit breakers can be operated by hand, major models have solenoids to activate the process and electric motors to regenerate power to the springs. The circuit breaker connections must carry the load current without having an extreme heating problem, and they must definitely withstand the temperature of the arc created whenever there is an interruption in the circuit. Connections are constructed of copper or copper metals, silver alloys, and other extremely conductive products. The bearing life of the connections is restricted by the breakdown of the contact substance due to the arc while the current in the circuit is interrupted. Some circuits are not generally used when connections are deteriorated, such as in miniature and molded case circuit breakers, however power circuit breakers and high voltage circuit breakers now have interchangeable connections. During short circuits, circuit breakers play a vital role and protect the circuit by heating or damaging it. Circuit breakers generally have standard current ratings, specific trip settings, and time-delay operations (typically less than 100 milliseconds). Common types of circuit breakers include low voltage circuit breakers,
An isolating switch is part of an electrical circuit and is most often found in industrial applications. The switch does exactly what its name suggests, in that it electrically isolates the circuit(s) that are connected to it. Such a switch is not normally used as an instrument to turn the circuit on/off in the way that a light switch does. It is unloaded or without charging device. It is mainly found in heavy industry. It is operated to disconnect the electrical system from the main supply for maintenance activities. It is an additional security device. The trapped charge will be grounded through its ground terminal. It is normally placed after the circuit breaker.
- Circuit breaker is a loaded device while on the other hand isolator is a loaded device. It means that the circuit breaker operates when the line is energized and any fault occurs. While the isolator will be operated manually when it is ensured that the system or line is de-energized.
- The circuit breaker is automatically operated by a relay or electromechanical mechanism, while the isolator is manually operated.
- In a system, if both the circuit breaker and isolator are installed and maintenance is needed on either piece of equipment, the circuit breaker will be tripped first, then the isolator will be manually operated.
- When the circuit breaker trips the circuit, a large spark is produced which is extinguished by the use of an extinguishing medium, i.e. SF6, gas, etc. When the isolator is operated and the equipment is isolated, no spark occurs.