Schneider REL52020 Easergy P3U Numerical Protection Relay

The Schneider REL52020 Easergy P3U Numerical Protection Relay is intended for feeder protection and monitoring in medium-voltage distribution systems. This version is configured with 3 CT ring lug inputs, 1 residual current input, 4 voltage inputs, 16 digital inputs, and 8 digital outputs, making it suitable for a wide range of protection and control applications.

One of the key features of the REL52020 is its low-voltage auxiliary supply range of 24–48 V AC/DC along with 24 V digital inputs. This makes it particularly suitable for substations, renewable energy projects, battery-backed control systems, and installations where low-voltage control circuits are used. The relay can be integrated into existing protection schemes without the need for additional voltage conversion equipment.

The relay continuously monitors current, voltage, and earth fault conditions and records events that can assist during fault investigation and maintenance activities. RS485 communication allows connection to SCADA and automation systems for remote monitoring, data collection, and operational control.

Specifications

• Manufacturer: Schneider Electric
• Product Series: Easergy P3
• Model: P3U
• Part Number: REL52020
• Relay Type: Numerical Protection Relay
• Protection Application: Feeder Protection
• Current Inputs: 3 CT Ring Lug
• Residual Current Input: 1 Io
• Voltage Inputs: 4 VT
• Digital Inputs: 16 DI
• Digital Outputs: 8 DO
• Auxiliary Supply Voltage: 24–48 V AC/DC
• Digital Input Voltage: 24 V
• Communication Interface: RS485
• Mounting: Protection and Control Panels

Features

• Numerical relay for feeder protection applications.
• 24–48 V auxiliary supply for low-voltage control systems.
• 24 V digital inputs for direct integration with low-voltage signalling circuits.
• Ring lug CT terminals for secure field wiring connections.
• Residual current monitoring for earth fault protection.
• RS485 communication for SCADA and automation integration.
• Event logging and fault recording functions.
• Suitable for new installations as well as retrofit projects.

Applications

• Feeder Protection
• Distribution Substations
• Renewable Energy Projects
• Solar and Wind Power Systems
• Industrial Power Distribution
• Utility Networks
• Protection and Control Panels
• SCADA Integrated Systems

The Schneider REL52020 Easergy P3U is often selected for installations that operate on 24 V control circuits and require dependable feeder protection with RS485 communication.