What is the primary purpose of an isolating switch?

The primary purpose of an isolating switch is to cut off the electrical circuit from the power source. This function is critical for ensuring safety during maintenance and repair operations. By disconnecting the circuit, the isolating switch helps to prevent accidental energization of electrical equipment, allowing workers to perform their tasks without the risk of electric shock.

In addition, isolating switches are designed to provide a visible break in the circuit, which serves as an indication that the system is de-energized. This visibility is essential for safety protocols in electrical work, as it allows technicians to confirm that the equipment is safe to handle.

While the other options may relate to various functions of electrical components, they do not capture the primary role of an isolating switch. Increasing circuit capacity pertains to systems designed for higher loads, changing current direction relates to switches or circuits that can alternate the flow of electricity, and preventing overload conditions is more aligned with circuit protection devices such as fuses or circuit breakers. Ultimately, the isolating switch is specifically designed for safe disconnection from the power source, underscoring its importance in electrical safety.