Understanding the Difference Between Contactors and Relays

Contact.Starters.Relay_GroupRelays and contactors are two of the most commonly used components in electrical circuits, but they have some major differences that should be considered before selecting one or the other.

What’s the Difference Between a Contactor and a Relay?


A relay is a switch that opens and closes an electrical circuit when triggered by an outside source and is usually triggered by a voltage or current level. A relay consists of an electromagnet that, when energized, closes the contacts to complete the circuit. Relays are commonly used in applications such as motor control and switching circuits on and off.


A contactor is similar to a relay but designed for larger loads. Contactors are typically used for controlling electric motors, lighting circuits, and other high-power applications. Whereas relays are activated by an outside source, contactors have a built-in control system which can be activated from multiple sources such as a manual switch, voltage or current level.

Another critical difference between the two is that contactors are typically larger than relays due to their larger load capacity. Relays come in various sizes and can be used in small or large applications, whereas contactors are generally limited to electrical circuits with high power requirements.

Key Considerations When Choosing Between Relays and Contactors

When deciding between relays and contactors for a specific application, it is crucial to consider various factors. One important consideration is the load size that needs to be controlled. Additionally, it is essential to consider environmental factors such as temperature, vibration, and any other conditions that might impact the performance and longevity of the chosen component. By carefully evaluating these factors, one can make an informed decision to ensure optimal control and reliability in the given application.

Regarding managing electrical loads, contactors and relays can play an important role depending on the application. Springer Controls has a full range of contactors and relays for all your control equipment needs. Contact us to find the right component for your project!