Products Relays

L-PRO 4000 Transmission Line Protection Relay
with IEC 61850 Station Bus Protocol

L-PRO 4000 Transmission Line Protection Relay with IEC 61850 Station Bus Protocol

The L-PRO 4000 is a digital, microprocessor-based line distance protection system that provides comprehensive distance based line protection for medium to extra-high-voltage transmission lines. Apply the L-PRO 4000 system for high-speed distance and directional protection and complete control in multi-breaker applications typically found in ring or breaker-and-a-half substation arrangements.


  • Primary and backup protection on transmission and sub-transmission lines (using pilot protection schemes)
  • Overhead lines and underground cables
  • Fully integrated breaker protection and control for 2 breakers
  • Single and multi breaker applications (i.e. ring-bus and breaker-and-a-half capability, including breaker failure and individual breaker monitoring requiring single pole/three-pole auto-reclosing)
  • Backup protection for generators, transformers and reactors

Features and Benefits

  • Ideal for multi-circuit line applications (to monitor mutual coupling via additional VT and CT inputs)
  • Ultimate flexibility with selectable “Single Pole”, “3 Pole” and “Single and 3 Pole” tripping and reclosing
  • Competitive operating speed (1.0 to 1.3 cycle operation at 80% reach, ideal for transmission line applications)
  • Flexible Communications
    • State-of-the-art communications (2 rear ports, 100BASE-TX RJ-45 or 100BASE-FX 1300 nm multimode optical with ST style connector to accommodate the industry’s latest network-based communications)
    • Ethernet ports with 2 unique MAC addresses that easily accommodate network access security needs
    • Front panel USB and 100BASE-TX RJ-45 Ethernet port interfaces (readily accommodate modern standard laptops)
  • Reduced Cost
    • Substation automation cost – includes IEC61850 protocol to display and transfer operational data via local-area network (LAN) for local HMI and wide-area network (WAN) for remote monitoring SCADA
    • Substation engineering, installation and commissioning cost and times – IEC 61850 GOOSE messages communicate high-speed information between IED’s on the substation LAN (including transfer trips, interlocking, load-shedding, and commands)
    • Product setting time – 240 x 128 LCD graphical user interface provides convenient means to check/change specific settings and parameters
  • Improved Overall Response Time
    • Expedited response to systems events (11 generic front panel LEDs can be mapped to internal elements) allowing operators to quickly identify the cause of system events
  • L-PRO screen Easy to Use
    • Flexible programmable logic for building customized schemes with ProLogic™ statements – 24 control logic statements (total of 192 statements)
    • User-friendly, Windows®-based relay setting and record analysis software
    • Enhanced DNP3.0 Level 2 SCADA communication protocol including user-selectable point lists, class support and multiple master station support
    • Exceptional fault recording capabilities with 96 s/cycle, all channels with events (best combination of waveform accuracy and file size)

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Winnipeg, Canada