Siemens 3RQ4118-2AM00 Plug-In Coupling Relay, 24V DC, 1CO Contact, Push-In Terminal

The Siemens 3RQ4118-2AM00 is a high-performance plug-in coupling relay engineered for demanding industrial automation environments. This compact device serves as a reliable interface between electronic control systems and field-level components, ensuring precise signal switching and galvanic isolation. With its slim 6.2mm profile, it is optimized for high-density mounting in control cabinets, allowing for efficient space utilization without compromising on electrical performance or safety.

Advantages

The primary benefit of this coupling relay is its advanced Push-In connection technology, which significantly reduces installation time and ensures vibration-resistant wiring without the need for specialized tools. The slim design allows for a high packing density, making it ideal for modern control panels where space is at a premium. Furthermore, the relay provides robust galvanic isolation, protecting sensitive control electronics from voltage spikes and interference originating from the load side, while the 6A thermal current rating ensures versatility across a wide range of switching applications.

Suitable for

• Industrial automation and control systems
• Signal isolation between PLC outputs and field devices
• Switching small to medium-sized loads
• Space-constrained control cabinet installations

This relay may not be suitable for applications requiring high-power switching beyond its 6A thermal current rating or for environments with extreme environmental conditions that exceed the specified protection class. It is also not intended for direct motor starting of large inductive loads without appropriate suppression circuitry.

Key specifications

• Operating voltage: 24V DC
• Contact configuration: 1 change-over (1CO) contact
• Thermal current: 6A
• Connection type: Push-in (spring-loaded) terminals
• Housing width: 6.2mm

To install the relay, insert it into a compatible base or terminal block until it clicks securely into place. Connect the 24V DC control signal to the input terminals and wire the load circuit to the change-over contact terminals using the push-in mechanism. Ensure that the wire ends are properly stripped according to the manufacturer's guidelines to guarantee a secure and reliable connection. Always verify that the control voltage matches the relay specifications before powering the system.

What to consider before purchase

• Ensure the 24V DC control voltage is compatible with your existing PLC or controller output.
• Verify that the 6A thermal current rating is sufficient for your specific load requirements.
• Confirm that the 6.2mm width fits your current DIN rail or terminal block configuration.
• Check the environmental conditions of the installation site to ensure they fall within the operating limits.

For optimal performance and longevity, ensure that the relay is installed in a clean, dry environment and that all connections are checked for tightness during periodic maintenance. Avoid exceeding the maximum switching frequency to prevent premature contact wear.