Red Seal Industrial Electrician Practice Exam

What is the role of relays in industrial circuits?

1. To store electrical energy

2. To act as switches in response to electrical signals

3. To amplify electrical signals

4. To convert alternating current to direct current

The correct answer is: To act as switches in response to electrical signals

Relays play a crucial role in industrial circuits primarily by acting as switches that operate in response to electrical signals. When a relay is energized by a control signal, it closes or opens its contacts, thereby controlling the flow of electricity in the circuit. This functionality allows for low-power circuits to control high-power devices, making relays essential for automation and control systems in various industrial applications. Their ability to control larger loads with a small input signal makes them particularly valuable for issues like safety, control, and switching mechanisms. Furthermore, relays can be utilized for various purposes, such as operation in timers, safety interlocks, or logic circuits, all of which rely on their switching capabilities.