REL-IR-BL/L-24DC/4X21 – Phoenix Contact Safety Relay Module for Automation

The REL-IR-BL/L-24DC/4X21 is a compact, durable, and highly efficient safety relay module manufactured by Phoenix Contact. Engineered specifically for industrial automation systems, this module is also widely recognized as a glass relay due to its transparent housing. With 4 changeover (4PDT) contacts and a 24V DC coil, it ensures reliable switching and consistent performance in safety-critical applications.

This plug-in industrial relay is not only easy to install but also easy to maintain. The integrated test button, mechanical status indicator, and built-in LED allow for real-time status monitoring and quick diagnostics. As a result, it minimizes downtime and supports faster troubleshooting during maintenance.

Moreover, its robust glass relay design enables quick visual inspections, while its compatibility with control panels, PLCs, and interface modules makes it an excellent fit for a wide range of automation setups. Because of its versatility and safety, the REL-IR-BL/L-24DC/4X21 is ideal for engineers and system integrators looking to improve operational reliability.

Key Features:

• Primary Function: High-quality safety relay module with 4 changeover contacts (4PDT)

• Brand: Phoenix Contact

• Coil Voltage: 24V DC for safe and energy-efficient operation

• Design: Transparent glass relay housing for easy visual inspection

• Indicators: Built-in LED and mechanical display for real-time relay status

• Diagnostics: Test button for simple, on-site testing and maintenance

• Mounting: Plug-in style for quick installation and easy replacement

• Applications: Ideal for control panels, PLC systems, and interface modules in industrial automation

• Standards: Compliant with EN 61810-1 and rated for high dielectric strength (2.5 kVrms)

• Temperature Range: Operates between -40°C to +70°C, suitable for harsh environments

Why Choose REL-IR-BL/L-24DC/4X21?

• Because it delivers both safety and reliability in automation environments

• Since it’s easy to install and compatible with a wide range of industrial systems

• As a control panel relay, it offers seamless integration and long-term performance

• Its plug-in industrial relay design significantly reduces downtime during replacement

• With a glass relay housing, it allows technicians to visually confirm status instantly

Technical Highlights:

• Contact Type: 4 changeover contacts (4PDT)

• Contact Material: Silver Nickel (AgNi)

• Rated Voltage: Up to 250V AC/DC

• Rated Current: 12 A

• Inrush Current: Max. 24 A (N/O contacts)

• Minimum Switching Current: 10 mA (12 V)

• Switching Capacity: Min. 120 mW

• Dimensions: 22.5 mm (W) × 28 mm (H) × 35.5 mm (D)

• Mounting: Compatible with standard industrial sockets

Conclusion:

The REL-IR-BL/L-24DC/4X21 by Phoenix Contact is more than just a safety relay—it is a critical component for improving automation reliability and control. Its smart glass relay design, combined with ease of diagnostics and robust performance, makes it a top choice for automation professionals. Whether you’re upgrading a control panel or building a new system, this plug-in industrial relay is the dependable solution you need.