HighPROTEC Line – MRU4
Outstanding solution for reliable protection
The MRU4 is a protection relay which uses the latest Dual-Core-Processor Technology to provide precise and reliable protective functions and is very easy to operate.
It is designed to protect electrical equipment from dangerous voltage fluctuations. For example protection against under voltages caused by mains short-circuits, or overvoltage’s
due to load shedding or failure of a generator voltage controller.
Its compact design makes the MRU4 ideal for installation within the LV terminal compartments of compact SF6-insulated MV systems. The protection functions of the MRU4 have been
adapted to comply with the requirements of the VDE‑AR‑N 4110: 2023-09.
- Communication & Connectivity
- Dual Ethernet channels for redundancy
- Supports RJ45 (electrical) and fiber optic interfaces
- Integrated test sockets for easy diagnostics
- Protection Functions
- Overcurrent protection (1A & 5A CT measurement)
- Earth fault protection
- Voltage & frequency protection
- Unbalanced load protection (2 elements)
- Thermal replica & inrush current handling
- Automatic reclosing
- Plausibility checks for reliable operation
- Adaptive parameter sets
- Data & Analysis
- Comprehensive RMS & DFT measurement values
- Disturbance record analysis software included
- Hardware & Design
- Wide-range power supply: 24VDC–270VDC / 48VAC–230VAC
- IP54 front protection
- Plug-type terminals for easy wiring
- Supports flush or door mounting
- Approvals
- Marine approvals (e.g., Lloyd’s Register)
- KEMA type tested
- Usability
- Masking of unused functions
- Multiple password levels for security
- Generator Protection: Safeguarding generators from issues like voltage controller failure or load shedding, including differential and generator-to-system synchronism check functions.
- Feeder and Mains Protection: Used for incoming and outgoing feeders in medium voltage systems, ensuring stability in distribution networks.
- Busbar Protection: Monitoring busbars for abnormal voltage and frequency conditions.
- General
- Device Type: Voltage and Frequency Protection Relay
- Processor: Latest dual-core processor technology
- Power Supply: Wide-range 24–270 VDC / 48–230 VAC
- Electrical Inputs
- Voltage Inputs: 4 inputs (0–800 V), automatic CT disconnect
- Under UL: max 600 V
- Current Inputs: Not available (MRU4 has no current measuring inputs)
- Communication & Networking
- Protocols Supported:
- IEC 61850, Modbus RTU/TCP
- Profibus DP
- DNP 3.0
- IEC 60870-5-103 / 104
- Ethernet: Dual redundant channels (RJ45 or Optical)
- Supports RSTP, PRP, HSR
- Time Synchronization: SNTP, IRIG-B00X
- Recording & Data Logging
- Disturbance Recorder: 120 seconds
- Fault Recorder: Stores up to 20 faults
- Event Recorder: 300 event logs
- Trend Recorder: 4000 entries
- Mechanical & Design
- Housing: IP54 front protection
- Mounting Options: DIN-rail, 19″ rack, or door mounting
- Approvals & Compliance
- KEMA Type Tested (IEC 60255-1:2009)
- UL508, CSA-C22.2 No.14
- Lloyd’s Register certified
- VDE-AR-N 4110 compliant
