Phoenix Contact Relays | PLC-RSC and PLC-RPT Series Selection Guide and Recommendations

In modern industrial automation systems, relay modules are essential for signal control, electrical isolation, and equipment protection.
Phoenix Contact, a global leader in electrical connection and automation technology, offers reliable and durable relay solutions for a wide range of industrial applications.

Among them, the PLC-RSC and PLC-RPT series are the most popular and widely used relay families, designed to meet demanding requirements in machine control, building automation, power systems, and process control.

Key Advantages of Phoenix Contact Relays

1. High Reliability and Durability

Made from premium contact materials and robust housings, Phoenix Contact relays deliver long service life and stable performance — even in harsh environments or high switching cycles.

2. Compact and Easy Installation

DIN-rail mounting design saves space in control cabinets and ensures easy integration with Phoenix Contact terminal systems.

3. Wide Voltage Range

Available for 12VDC, 24VDC, 24UC, 48DC, 60DC, 120UC, and 230UC, covering both DC and universal AC/DC control voltages.

4. Modular Design and Plug-In Relays

The modular plug-in design allows for easy maintenance, quick replacement, and seamless system expansion — reducing downtime and maintenance costs.

1. PLC-RSC Series — Universal Industrial Relay Modules

The PLC-RSC series is one of Phoenix Contact’s classic universal relay module lines.
It’s ideal for PLC output isolation, signal switching, and industrial control applications.

These modules feature plug-in relays, integrated LED indicators, and various contact types to suit diverse requirements.

Popular Models:

Common Applications:

• PLC output isolation

• Control of solenoid valves and small motors

• Alarm and monitoring systems

• Industrial signal routing and load switching

2. PLC-RPT Series — High-Performance Industrial Relay Modules

The PLC-RPT series is designed for high-load and long-life operation, serving as the ideal intermediate relay in industrial control systems.
It offers a variety of coil voltages, contact configurations, and plug-in options to meet different application needs.

Popular Models:

Common Applications:

• Signal isolation and amplification

• High-current load switching

• Safety and interlock circuits

• Power control and monitoring systems

Relay Selection Tips

1. Define Your Control Voltage and Load Type

• For PLC outputs, choose 24DC models.

• For universal AC/DC control, use UC-type models (e.g., 24UC, 120UC, 230UC).

2. Select Contact Type and Load Capacity

• SPDT (Single Pole Double Throw) → For basic switching control.

• DPDT (Double Pole Double Throw) → For multi-circuit or interlock applications.

3. Match to Your Application Environment

• HC (High Capacity) → For frequent switching or higher load currents.

• AU (Gold-Plated Contacts) → For low-level signal control.

• EX (Explosion-Proof) → For hazardous or chemical environments.

4. Installation and Maintenance

All Phoenix Contact PLC relay modules are DIN-rail mountable, with LED indicators and bridge connectors available for simplified wiring and diagnostics.

Conclusion

Whether you’re designing a PLC control panel, industrial automation system, or power protection circuit,
Phoenix Contact PLC-RSC and PLC-RPT relay modules deliver outstanding reliability, safety, and flexibility.

Benefits Summary:

• Long-lasting and stable performance

• Wide range of voltage and contact options

• Easy installation and maintenance

• Compatible with various industrial control systems

Contact Us

Need help selecting the right Phoenix Contact relay model for your project?
Our technical team is here to assist you!