Reed Switches used in a Reed Relay Application

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• Introduction
• What is a Reed Relay?
• How Does a Reed Relay Work in Practice?
• Key Features of Reed Relay Applications
• Advantages of Using Reed Relays Over Other Technologies
• Common Reed Relays Applications by Industry
• Conclusion

Introduction

Reed switches used in a reed relay application are critical for achieving precise, low‑level switching in modern electronic systems. A reed relay combines the hermetically sealed reliability of reed switches with an electromagnetic coil, making it ideal for applications that demand high insulation resistance, low contact resistance, and long operational life.

In this article, we explain what a reed relay is, how a reed relay works, and why reed relay applications are preferred in industries such as automotive electrification, medical, renewable energy, and test equipment.

What is a Reed Relay?

A reed relay is a type of relay that uses an electromagnetic coil to operate one or up to eight reed switches. The reed switch or switches are typically inside the relay’s coil. Insulated copper wire either wound around a bobbin or self-contained makes up the coil.

How Does a Reed Relay Work in Practice?

The most basic reed relay operates with a few simple steps. First and foremost, the relays’ electromagnetic coil generates current when voltage is applied. Next, the coil’s current produces a magnetic field that closes the reed switch contacts. Finally, removing the voltage from the coil opens the switch contacts.

Furthermore, reed relays can work in far more advanced ways. For example, an RF reed relay application is designed to switch high frequency signals. Placing a coaxial shield around the reed switch or switches allows the relay to switch signals up to 7 GHz. For more reed relay application examples, jump to the section: Where are Reed Relays Used?

Key Features of Reed Relay Applications

Reed relay features outperform semiconductor and electromechanical relays in several critical areas:

Reed relays offer a lot more features and advantages over other relays. Check out some of these features in the below list.

Advantages of Using Reed Relays Over Other Technologies

Reed Relays offer a wide range of unique switching advantages, including:

Common Reed Relay Applications by Industry

Because of these advantages, reed relay applications are commonly found in environments where accuracy, safety, and long‑term reliability are non‑negotiable. For instance, below is a list of some common reed relay application examples.

 Applications

• Battery management and conditioning systems in cars, especially in electric and hybrid
• High voltage insulation in renewable energy, photovoltaic, solar, and power distribution systems
• Voltage isolation in medical equipment such as surgical generators and automated external defibrillators
• High density matrices in test equipment, integrated circuit, and precision testers, as well as multiplexers
• Intrinsic safety in mining, oil and gas production, and geothermal and seismic instruments

Conclusion

Reed relays solve low‑level switching challenges that other relay technologies cannot. They provide high‑voltage and high‑frequency performance while maintaining the ability to reliably switch extremely low voltages and currents over a long operational lifetime.

Standex Detect designs custom reed relay solutions in a wide range of packages optimized for demanding applications. If you are designing a system that requires precise, reliable switching, contact our relay experts to discuss the right reed relay application for your needs.