Schneider REL52021 Easergy P3U Numerical Protection Relay
The Schneider REL52021 Easergy P3U Numerical Protection Relay is designed for feeder protection in medium-voltage distribution networks. This configuration includes 3 ring lug CT inputs, 1 residual current input, 4 voltage inputs, 16 digital inputs, and 8 digital outputs, providing the measurement and control functions required in modern protection schemes.
A key feature of the REL52021 is its dual LC fibre-optic communication ports. Fibre communication is often preferred in substations and industrial environments where long communication distances, electromagnetic interference immunity, and network reliability are important. The relay can be connected directly to fibre-based SCADA and substation automation networks without requiring separate media converters.
The relay supports 110 V digital inputs and a wide 48–230 V AC/DC auxiliary supply range, making it suitable for a variety of control and signalling systems. Ring lug CT terminals provide secure wiring connections and are commonly used in switchgear retrofits, panel upgrades, and utility applications.
Specifications
- Manufacturer: Schneider Electric
- Product Series: Easergy P3
- Model: P3U
- Part Number: REL52021
- 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: 48–230 V AC/DC
- Digital Input Voltage: 110 V
- Communication Ports: 2 × LC Fibre Optic
- Mounting Application: Protection and Control Panels
Features
- Numerical protection relay for feeder applications.
- Dual LC fibre-optic ports for high-speed communication.
- Suitable for fibre-based SCADA and automation networks.
- Ring lug CT terminals for secure field wiring.
- Residual current monitoring for earth fault protection.
- 110 V digital inputs for protection and control circuits.
- Event logging and fault recording functions.
- Wide auxiliary supply range for installation flexibility.
Applications
- Feeder Protection
- Distribution Substations
- Utility Power Networks
- Industrial Power Distribution Systems
- Electrical Protection Panels
- Substation Automation Systems
- Fibre-Optic Communication Networks
- Infrastructure and Energy Projects
The Schneider REL52021 Easergy P3U is commonly used in installations where feeder protection and fibre-optic communication are required within the same protection relay platform.
