Siemens SIPROTEC 5 7VK87 Breaker Failure Protection Relay

The Siemens SIPROTEC 5 7VK87 is a high-end modular breaker failure protection relay designed to ensure reliable operation of circuit breakers in medium-, high-, and extra-high-voltage substations. Built on the advanced SIPROTEC 5 platform, it provides fast and secure detection of breaker failure conditions and initiates backup tripping to isolate faults and maintain system stability.

The relay continuously monitors breaker operation and detects failure scenarios such as failure to trip or interruption of fault current. In such cases, it rapidly issues backup tripping commands to adjacent breakers, preventing fault propagation and minimizing damage to equipment.

With its modular and scalable I/O architecture, the 7VK87 supports flexible configuration for different substation layouts. It integrates protection, control, automation, and monitoring functions into a single device, making it an ideal solution for modern digital substations.

Engineered with DIGSI 5 and supporting IEC 61850 communication, the relay enables seamless integration, high-speed communication, and advanced automation with strong cybersecurity features.

Main Function

• Breaker Failure Protection

Tripping

• Backup tripping of adjacent circuit breakers
• High-speed fault clearing

Technical Specifications

Protection & Functional Features

• Breaker failure protection for:
  • Circuit breakers in HV/EHV substations
• Detects:
  • Failure to open (trip failure)
  • Failure to interrupt fault current
• Initiates:
  • Backup tripping of adjacent breakers
• High-speed operation ensures:
  • Rapid fault isolation
  • Prevention of system instability
• Can be integrated with:
  • Line protection
  • Transformer protection
  • Busbar protection schemes

Hardware & Modular Design

• Fully modular and expandable I/O configuration
• Flexible configuration for various substation schemes
• Typical configurations:
  • Binary inputs: ~5 to 31
  • Binary outputs: ~8 to 46
• Scalable design for future expansion
• Conformal coating for harsh environments

Communication & Protocols

• IEC 61850 Edition 1 / 2 / 2.1 compliant
• GOOSE messaging for high-speed inter-relay communication
• Supports:
  • PRP / HSR redundancy
  • Modbus TCP, DNP3
• Enables seamless integration into digital substations

Engineering & Software

• Configurable via DIGSI 5 engineering tool
• Graphical logic configuration (CFC)
• Integration of protection, control, and automation
• Simplified commissioning, testing, and diagnostics

Advanced / Latest Features (2024–2026 Update)

• Web-based user interface for monitoring and diagnostics
• Advanced cybersecurity:
  • Role-based access control (RBAC)
  • Secure firmware and communication
• Digital Twin support for simulation and testing
• Process bus ready (Sampled Values support)
• High availability with redundant communication architecture

Applications

• Breaker failure protection in HV/EHV substations
• Utility substations
• Industrial power systems
• Integration with:
  • Line protection schemes
  • Transformer protection
  • Busbar protection systems