What is a Relay Used For, and Why Do You Need One?

A relay is an electrically operated switch. It comes to life when an external electrical signal is received, which activates a coil within the relay. This coil then either opens or closes the circuit, enabling or disabling the flow of electricity, much like a runner in a relay race would either continue the race or stop based on receiving the baton. The relay, by opening or closing the electrical circuit, governs the onward journey of the electrical signal, directing it to other equipment or halting its progress. Below, we explain the advantages of relays and answer the common question: “What is a relay used for?”

Types of Electrical Relays

They may come in different shapes and sizes, each tailored for specific tasks, but the two primary types are Mechanical and Solid State Relays (SSR).

1. Mechanical Relays

These traditional relays have physical moving parts that open or close the circuit.

  • General purpose relays: Commonly used for applications requiring simple on/off control.
  • Latching relays: These relays maintain their position (open or closed) even after removing the control power, ensuring energy conservation.
  • Reed relays: Characterized by their sealed contacts within a glass tube, they are compact and reliable, often preferred in many low-voltage applications.

2. Solid State Relays (SSR)

Solid State Relays, or SSRs, use semiconductor technology instead of moving parts. This makes them fast and efficient in switching. They are the favorites for tasks that are delicate or have a high frequency, especially when accuracy is a big deal. SSRs are reliable for a long time, work quietly, and don’t create much electromagnetic disturbance. So, in places where control needs to be just right, SSRs fit well.

What Is a Relay Used For?

They may be at the heart of many control systems, acting as the bridge between electronic controllers and high-power devices, but what is a relay used for exactly, and how can you use them in both simple and complex applications? Here’s a quick overview:

  • Industrial control systems. Relays keep machinery and processing lines running smoothly. How? By regulating power flow.
  • Automation systems. Precision control is key in automated processes. Enter relays and their reliable switching.
  • Home appliances. Many common appliances rely on relays for crucial operations — think cycle control in washing machines or temperature regulation in ovens.
  • Automotive systems. Relays are widely used for managing power distribution and ensuring the reliability of critical systems, i.e., brakes and power steering.
  • Safety systems. Relays offer dependable isolation and switching in safety-critical systems.
  • Telecommunication equipment. With a role in signal routing and switching, relays help keep the lines of communication open.

How To Use a Relay and Why

Employing a relay connects the control circuit to the relay coil and the device you aim to manage to the relay switch. Once the control circuit is live, the relay coil springs into action, directing the relay switch to govern your device precisely. This simple yet effective mechanism is why relays are cherished in electrical setups.

  • Energy conservation — only a small voltage is needed to control larger loads.
  • Safety barrier — controlling hazardous voltages independently.
  • Cost-effective and efficient — a wise pick for many electrical applications.

Contact Solid State Inc.

Discover a broad spectrum of reliable relays tailored for diverse applications at Solid State Inc. More than happy and ready to meet your unique needs, we are your go-to for quality assurance and timely delivery. Browse our extensive relay selection or reach out to our experienced team today for bespoke solutions.