ALSTOM EP3-E-4-EN Multi functional protection relay

ALSTOM EP3-E-4-EN Technical Overview

1. General Description

The EP3-E-4-EN is a multi-function protection relay optimized for medium- and low-voltage electrical systems. It integrates advanced protection, monitoring, and communication features to ensure reliable fault detection and system stability. This relay is commonly used in substations, industrial plants, and renewable energy installations.

2. Key Technical Specifications

• Electrical Ratings
  • Rated Voltage: 110–690V AC (phase-to-phase); up to 36kV via voltage transformers (VTs).
  • Current Inputs: Configurable for 1A or 5A secondary CTs.
  • Frequency: 50/60 Hz (±2% accuracy).
  • Auxiliary Power: 24–250V DC/AC (±20%).
• Protection Functions
  • Overcurrent Protection: Definite/Inverse Time (IEC 60255, ANSI C37.90 curves).
  • Earth Fault Protection: Sensitive directional/non-directional (50/51N, 50/51G).
  • Voltage Protection: Over/undervoltage (27/59), phase sequence (47).
  • Motor-Specific Protections: Thermal overload (49), stall prevention, unbalance (46).
  • Advanced Features: Frequency protection (81O/U), harmonic analysis (THD).
• Communication & Interfaces
  • Protocols: Modbus RTU, IEC 60870-5-103/104, or IEC 61850 (if enabled).
  • Digital I/O: Programmable contacts for tripping, alarms, and remote control.
  • HMI: Backlit LCD with keypad for local configuration.
• Environmental & Mechanical
  • Operating Temperature: -25°C to +70°C (-13°F to +158°F).
  • Enclosure: IP40 (standard) or IP54 (optional ruggedized version).
  • Mounting: DIN rail or panel-mounted (modular design).
• Certifications
  • Standards: IEC 60255, EN 50178, CE Mark, UL 508.

3. Functional Capabilities

1. Adaptive Protection Logic
   • Configurable trip curves and thresholds via software (e.g., MiCOM S1 Studio).
   • Support for custom logic equations for complex automation sequences.
2. Fault Recording & Diagnostics
   • Event Log: Stores 512+ time-stamped events (fault type, magnitude, duration).
   • Waveform Capture: Records pre- and post-fault current/voltage waveforms.
3. Grid Interaction
   • Automatic Recloser (79): Restores power after transient faults.
   • Load Shedding: Prevents overloads by prioritizing critical loads.
4. Integration with SCADA/DCS
   • Real-time data transmission via IEC 61850 (GOOSE/SV) for smart grid applications.
   • Remote firmware updates and configuration via Ethernet/IP.
5. Self-Testing & Health Monitoring
   • Continuous diagnostics for CT/VT circuits, power supply, and relay logic.

4. Typical Applications

• Utility Substations: Protection of feeders, transformers, and busbars.
• Industrial Motors: Overload and phase loss protection for pumps, fans, and conveyors.
• Renewable Energy: Solar/Wind farm grid connection protection.
• Railway Electrification: Traction power supply and overhead line (OHL) systems.

5. Ordering Information

• Model: EP3-E-4-EN (confirm suffix details for voltage/communication options).
• Accessories: 
  • CT/VT modules (e.g., EP3-CT-5A).
  • Communication gateways (e.g., Modbus-to-IEC 61850 converters).
  • Mounting kits and DIN rail adapters.

Key Advantages

• High Accuracy: ±1% measurement accuracy for current and voltage.
• Flexibility: Modular firmware and hardware for future upgrades.
• Robustness: Designed to withstand harsh environments (dust, humidity, EMI).