An electrical isolator, also known as a disconnect switch or simply an isolator switch, is a crucial component in electrical systems and is primarily designed to provide electrical isolation between the source of power and the equipment or circuit it serves. Its main function is to disconnect the electrical supply to a particular circuit or piece of equipment when needed. Here are the key functions of an electrical isolator:
Isolation of circuits: The primary purpose of an isolator is to physically disconnect a circuit or equipment from the power source, ensuring that no electrical current flows through the isolated section. This is important during maintenance, repair, or troubleshooting activities, as it prevents accidental electric shocks and other hazards.
Safety: Isolators play a crucial role in enhancing the safety of personnel working on electrical systems. When a circuit or equipment is isolated, it reduces the risk of electric shock and provides a safe working environment for maintenance and repair personnel.
Switching and maintenance: During routine maintenance or repairs, it is essential to cut off the power supply to specific circuits or equipment. Isolators provide a convenient means of doing this, allowing technicians to work safely on electrical components without the risk of electrical accidents.
Emergency shutdown: In emergency situations, isolators can be used to quickly and safely shut down power to a particular area or equipment, preventing further damage or hazards.
Testing and diagnostics: Isolators enable effective testing and diagnostics of electrical systems. By isolating a specific circuit or equipment, engineers can analyze its performance without interference from other parts of the system.
Load shedding: In certain situations where power supply needs to be rationed or redistributed, isolators can be used to shed loads by disconnecting specific circuits or devices temporarily.
Overcurrent protection: In some cases, isolators may serve as a part of the overall overcurrent protection system, allowing them to interrupt the current flow when excessive current is detected.
It's important to note that isolators are not designed to interrupt the flow of current under load conditions regularly. Instead, they are primarily used for breaking and making circuits when they are not carrying current or are operating at minimal loads. For regularly switching circuits under load, specialized switches like circuit breakers are used, as they are designed to handle the load interruption safely.