Relays

Relays are essential electromechanical components that act as electrically controlled switches, enabling safe and efficient control of circuits and devices.

What Are Relays?

Relays are electromagnetic switches powered by a relatively small current. Thanks to their structure, they can either switch off or amplify a much larger current. Relay switches have been largely used in the telecommunications industry since the 19th century, as well as in the industrial and automotive sectors. Their application has now extended to computing and medical research, making them a fundamental component for devices used in everyday life.

How Does a General Purpose Relay Switch Work?

Relays work based on electromagnetic force. A relay's core consists of a coil of wire (commonly copper) that becomes magnetised when an electric current passes through it.

They function as a bridge between devices, receiving an input signal from one and transmitting an output to another. The electromagnetic current generated by the electrical input causes a set of contacts to open or close. In turn, these contacts control a separate, higher-power circuit, determining the transmission or the blockage of electrical signals.

Understanding Relay Types for Specific Applications

Different types of relays are suited for different applications:

Latching relays

Operated by a magnetic or mechanical system, latching relays feature a single or double-winding coil. They remain in their last position (open or closed) even after the control signal is removed, and are commonly used in applications where maintaining a specific state is required, such as automatic doors, lighting controls, and industrial automation.

Non-latching relays

These relays return to their initial position when the power is removed from the circuit. Non-latching relays are normally found in push-button applications like keyboards, where momentary switching is needed.

High-frequency and RF relays

These specialised relays are designed to handle high-frequency signals, commonly used in radio system, computing, testing and industrial equipment where high voltages are involved. An example of application is in radio devices, where relays separate the circuits responsible for receiving and transmitting high-frequency signals.

How to Choose the Right Relays

To choose the right relay, consider factors such as the required voltage and current ratings, the type of actuation (latching or non-latching), the number of contacts, the chosen electrical enclosure, and the environmental conditions of your intended use.

With a wide selection of quality relays products, RS Hong Kong has the products to meet these needs so that you can find the right relay for your application.

How to Order Relays from RS Hong Kong

RS Hong Kong is a trusted electromagnetic relay supplier, sourcing the best products from reputable brands, such as Panasonic, ABB, and Pilz. If you’re looking to buy relay products online, our user-friendly site and extensive catalogue promise to make the procurement process a breeze.

Beyond relays, we also stock a wide range of other electrical and industrial components, such as electrical switches and DIN rail terminal blocks, providing a comprehensive selection to meet your requirements. Need help in making your selection? Our informative articles, such as our C Battery guide, provide useful advice and tips to aid your decision.

How Delivery Works at RS Hong Kong

With flexible delivery options, RS Hong Kong ensures you receive your relay switch when and where you need them. Our efficient delivery services include options for express delivery and next-day delivery, catering to urgent requirements.

Please visit our delivery information page to find out more about our delivery options, estimated delivery times, and fees.