Isolator vs Circuit Breaker: What's the Differences?

Everyone understands the importance of electrical safety, yet many people are unaware of the types of electrical devices available on the market. Switchgear refers to all of the safety-enhancing devices that fall under this umbrella term. Circuit breakers and isolators/disconnectors are the two most common types of switchgear found in electric power systems. Electrical power systems cannot function without these two devices. 

In case of an electrical system malfunction, both circuit breakers and isolators are responsible for disrupting or isolating connections. Since the isolator and circuit breaker have such close functional relationships, many people confuse the two. This article explores the difference between circuit breakers and isolators in order to debunk this common misconception. These safety devices are essential, so let's learn more about them. Moreover, you can also check out FPGA vs Microcontroller and CR2 vs CR123. 

What is an Isolator?

Electrical isolators are devices used for separating sections of circuits from the main power source for safety and maintenance reasons. This system allows service or inspection of a specific part of the system without risking electric shock or other hazards. In electrical systems that carry high voltages, industrial machinery, and other applications, isolation is commonly used. As a result, no current can flow to the isolated section because the electrical connection is physically broken. Using this method, technicians are not at risk of accidentally energizing the system while working on it. Aside from that, isolators protect the integrity and safety of the entire electrical network by stopping electrical faults from propagating through the system.

What is a Circuit Breaker?

Overcurrent, typically caused by overloads or short circuits, can damage an electrical circuit if a circuit breaker is not properly installed. An automatic circuit breaker prevents electrical fires or equipment damage by interrupting electricity flow whenever a fault is detected. A circuit breaker can be reset manually or automatically after a fault condition has been resolved to resume normal operation. From residential to industrial wiring, they are available in different sizes and types. Electrical systems are made safer and more reliable by circuit breakers, which interrupt current flow reliably.

Difference between Isolator and Circuit Breaker

Function and Purpose:

• Isolator: In electrical circuits, an isolator isolates a part of the circuit from the main power supply by manually turning the switch. Maintenance and repair personnel are protected by it because a visible break in the circuit is provided during maintenance and repair. Overcurrents and short circuits cannot be handled by it.

• Circuit Breaker: In case of an overload or short circuit, a circuit breaker interrupts the flow of electricity automatically. By quickly cutting off power during unsafe conditions, it protects the electrical system and prevents equipment damage.

Operation:

• Isolator: The circuit must be opened or closed manually by a human being. Maintenance purposes require the isolation of the circuit, so it cannot be used when the circuit is under load.

• Circuit Breaker: The circuit is protected by an automatic trip mechanism that operates under load. After the fault is cleared, the device can be manually reset or automatically reset.

Load Handling:

• Isolator: Under load, a circuit cannot be opened or closed. If the circuit is not in use, it should be operated by the operator only when it is not being used.

• Circuit Breaker: In order to handle faults and protect the circuit during abnormal conditions, it interrupts current flow under load conditions.

Installation Location:

• Isolator: Provides a means of disconnecting power for maintenance or safety purposes, usually at an electrical circuit or system's input.

• Circuit Breaker: Provides ongoing protection against faults within the electrical circuit. Distribution panels and switchboards often contain this component.

Safety Features:

• Isolator: Ensures complete de-energization during maintenance by providing a visible means of isolation. Electrical faults are not protected.

• Circuit Breaker: Automatically interrupts power during faults to ensure the safety of the electrical system against overcurrent and short circuit conditions.

Usage:

• Isolator: For inspections and maintenance of equipment, these devices are primarily used in industrial and utility applications.

• Circuit Breaker: Protection from overcurrent and short circuit damage in residential, commercial, and industrial applications.

Applications

Isolators

Electrical Maintenance and Safety: Maintenance and repair work require isolators to ensure personnel safety. Electrical shocks and accidents are prevented by physically disconnecting sections of an electrical circuit, called isolators. In high-voltage systems where injuries are a significant risk, this visible disconnection ensures the circuit is safe for work.

Industrial Equipment Isolation: To perform routine maintenance or emergency repairs on heavy machinery and equipment, isolators are used in industrial settings. Any unintentional electric flow during maintenance could result in severe damage or injury in manufacturing, mining, and oil and gas fields, where machinery operates under high power loads.

Power Distribution Systems: Electricity distribution systems employ isolators to control and manage the flow of electricity. Substations, for example, use these devices to isolate different parts of the distribution network for maintenance or in case of a fault. Maintenance work can be performed without disrupting the entire network without causing any disruptions.

High Voltage Transmission Lines: It is crucial to segment high voltage transmission lines for maintenance and fault management that isolators are used. They enable maintenance crews to work safely by de-energizing specific sections of the transmission line. Weather, as well as high voltages, can be handled by a good insulation material.

Renewable Energy Systems: During maintenance and safety procedures on renewable energy systems, such as solar and wind power installations, isolators are used. Isolators allow solar panels to be disconnected from inverters and other electrical components, allowing them to be repaired and maintained safely.

Residential and Commercial Buildings: Combined with circuit breakers, isolators improve safety and manage electrical loads in both residential and commercial buildings. These switches are usually located in the main electrical panel. Maintenance and repairs can be completed safely without interrupting the power supply for the entire building.

Switching Operations: It is common to use isolation devices during routine switching operations to separate different sections of an electrical circuit. When there are multiple circuits interconnected in complex electrical networks, this is especially important. Using isolators prevents electrical hazards and short circuits from occurring during switching.

Circuit Breaker

Residential Electrical Systems: During a short circuit or overcurrent, circuit breakers protect electrical circuits in residential electrical systems. A circuit breaker controls how electricity flows through a house's main electrical panel, where it supplies electricity to different parts. They prevent potential electrical fires and protect household appliances by automatically shutting off power in case of a fault.

Commercial and Industrial Buildings: Electrical circuit breakers are essential components in commercial and industrial buildings as they provide power to lighting, heating, ventilation, air conditioning, and other vital systems. Electrical configurations are more complex and power loads are higher with industrial circuit breakers. The purpose of these devices is to ensure continuous operation, reduce downtime, and isolate faulty circuits so that troubleshooting and repairs can be performed safely and efficiently.

Power Distribution Networks: Power distribution networks are not reliable and safe without circuit breakers. To protect transformers, feeders, and other crucial components within the network, they are installed at various locations within the network, including substations. A circuit breaker quickly disconnects the affected section in the event of a fault, preventing equipment damage and maintaining the overall grid stability. For power supply continuity and fault management to be effective, this capability is crucial.

High Voltage Transmission Lines: Transmission lines are protected from widespread power outages by high voltage circuit breakers. High current interrupters are designed for severe operating conditions and are capable of interrupting very high currents. By isolating faults and minimizing the impact on power supply, they provide essential protection for the transmission infrastructure. Keeping large power transmission systems reliable and safe requires high voltage circuit breakers.

Renewable Energy Systems: Power flow is controlled and protected by circuit breakers in renewable energy installations, such as solar and wind power. A circuit breaker protects photovoltaic arrays and inverters from overcurrent conditions, for instance, in solar power systems. By preventing damage to the equipment and ensuring safety for maintenance personnel, they ensure that any faults in the system can be quickly isolated. Circuit breakers contribute to the reliability and efficiency of wind power systems by protecting turbines and electrical components from faults.

Motor Protection: In industrial applications, circuit breakers protect electric motors extensively. In addition to overloads, short circuits, and phase failures, motors are prone to malfunctions as well. Circuit breakers designed specifically for motor protection are known as motor protection circuit breakers (MPCBs). In the event of a fault, these devices interrupt the power supply to the motor to prevent motor damage. Various industrial processes require motors to be reliable and long-lasting.

Final Verdict

An isolator and a circuit breaker are both important components of an electrical system. The electrical appliances are protected against damage or faults by these devices. Furthermore, they play an important role in regulating conditions that are faulty. 

As far as their functions are concerned, these two mechanical devices have some similarities. They have many differences in terms of how they work, how they operate, the functions they perform, the parts they use, and countless other things. Therefore, to avoid any confusion, each one must be explained in detail. Blikai offers a wide range of electrical components for electronic equipment, so you can get a detailed insight into your kit.