Which device is essential for ensuring electrical isolation during repairs?

An isolator switch is crucial for ensuring electrical isolation during repairs because it is specifically designed to disconnect electrical circuits and provide a means of safely isolating equipment from the power source. This is essential for maintaining safety during maintenance or repair work, as it prevents accidental energization of the circuit, which could lead to severe injuries or electrical hazards.

Isolator switches can handle high voltage and current loads while offering a clear indication of whether the circuit is open or closed, giving technicians confidence that the circuit is de-energized. This function is vital in ensuring that when a technician is working on the electrical system, they can do so without the risk of electric shock or equipment damage, as they are assured the power is completely off.

Other devices like relays, capacitors, and diodes serve different purposes in electrical systems. Relays control circuits, capacitors store electrical energy, and diodes allow current to flow in one direction only. While these components are important in various applications, they do not provide the necessary isolation for safety during repair work, making the isolator switch the only suitable option for this specific requirement.