Product Overview

• Brand: DEIF A/S (a global provider of power control, monitoring, and automation solutions)
• Product Line: GPU (Generator Protection Unit) Series
• Type: Dedicated Generator Protection Relay/Module
• Industry: Marine (merchant ships, offshore vessels), power generation (diesel/gas gensets), industrial backup power (data centers, hospitals), and microgrids.
• Function: Acts as a standalone or integrated protection device for synchronous and asynchronous generators. It continuously monitors critical electrical and mechanical parameters of gensets to detect abnormal conditions (e.g., overcurrent, short circuits, voltage instability). When parameters exceed predefined safety thresholds, it triggers selective protection actions (e.g., tripping circuit breakers, activating alarms, shutting down the genset) to prevent equipment damage, fires, or electrical hazards. Unlike general-purpose controllers, it prioritizes fast response times for fault mitigation.

Key Features

1. Comprehensive Protection Functions
   • Covers a full range of generator-specific fault scenarios, categorized into electrical and mechanical protection:
     • Electrical Protection:
       • Overcurrent (OC): Protects against excessive current due to load surges or short circuits (includes inverse-time and definite-time curves).
       • Short-Circuit Protection (SC): Rapidly detects three-phase, phase-to-phase, or phase-to-ground short circuits (response time <50 ms).
       • Overvoltage (OV)/Undervoltage (UV): Triggers when generator output voltage exceeds/falls below safe limits (e.g., ±10% of rated voltage).
       • Overfrequency (OF)/Underfrequency (UF): Monitors grid frequency to prevent generator damage from overspeed/underspeed (critical for synchronous gensets).
       • Reverse Power (RP): Detects power flow reversal (e.g., genset acting as a motor) and trips the breaker to avoid mechanical stress.
       • Loss of Excitation (LOE): Protects synchronous generators from instability caused by excitation system failure.
     • Mechanical & Auxiliary Protection:
       • Low Lubricating Oil Pressure: Interfaces with pressure sensors to shut down the engine if oil pressure drops.
       • High Engine Temperature: Triggers alarm/shutdown via temperature sensor inputs (RTD/thermocouple).
       • Overspeed: Works with magnetic pickups (MPUs) to detect rotor overspeed (e.g., 115% of rated speed) and initiate emergency stop.
2. Fast Response & Selectivity
   • Equipped with a high-speed microprocessor for real-time data processing (sample rate up to 1 kHz per parameter), ensuring protection actions are triggered within milliseconds of fault detection.
   • Supports selective tripping to isolate only the faulty generator without disrupting the entire power system (critical for parallel genset configurations in marine or industrial grids).
3. Flexible Configuration & Integration
   • Configurable protection thresholds, time delays, and trip logic via DEIF’s PC-Tool software or local HMI (if equipped). This allows customization for different generator types (diesel/gas, synchronous/asynchronous) and application requirements.
   • Integrates with DEIF genset controllers (e.g., DGC-2020, DGC-300) and power management systems (PMS 300/400) via standard industrial protocols, enabling centralized monitoring and control.
4. Rugged Design for Harsh Environments
   • Built to withstand the demanding conditions of generator installations:
     • Marine-Grade Durability: Compliant with IEC 60945 (marine electronics) and certified by DNV GL, ABS, and LR for use in engine rooms and offshore platforms.
     • Industrial Immunity: Resistant to vibration (IEC 60068-2-6), shock (IEC 60068-2-27), and electromagnetic interference (EMC compliance with IEC 61000-6-2/4).

Key Specifications

1. Electrical Parameters
   • Power Supply: 24V DC (nominal, standard for DEIF modules), with a tolerance range of 18–32V DC. Optional 12V DC variant available for small gensets.
   • Power Consumption: ≤15W under full load (varies by active protection functions).
   • Input Signals:
     • Electrical Inputs: 3-phase voltage (100V/230V/400V AC), 3-phase current (via current transformers, CT ratio configurable), frequency (50/60 Hz).
     • Mechanical Inputs: 2–4 analog channels (4–20 mA) for oil pressure/temperature; 1–2 digital inputs for MPU speed signals.
   • Outputs:
     • Relay Outputs: 4–8 configurable relay contacts (2A @ 250V AC / 30V DC) for circuit breaker tripping, alarms, and genset shutdown.
     • Digital Outputs: 2–4 open-collector outputs for status signals.
2. Physical & Environmental Attributes
   • Form Factor: Rack-mount (19-inch, 1–2U) or DIN-rail mount design, compatible with standard control cabinets.
   • Dimensions: Estimated 483 mm (width) × 44 mm (height, 1U) × 180 mm (depth) for rack-mount models.
   • Environmental Ratings:
     • Operating Temperature: -25°C to +70°C (suits extreme climates from cold storage to hot engine rooms).
     • Humidity: 5–95% (non-condensing), resistant to moisture in marine/industrial settings.
     • Ingress Protection (IP): IP20 (when mounted in a cabinet) or IP65 (for standalone marine applications—model-dependent).
3. Communication & Monitoring
   • Protocols: Modbus RTU (RS-485), Modbus TCP (Ethernet), and CANopen for integration with controllers, HMs, and SCADA systems.
   • Local Monitoring: Optional LCD display with pushbuttons for real-time parameter viewing, alarm acknowledgment, and basic configuration (model-dependent).
   • Event Logging: Stores up to 500 timestamped fault events (e.g., overcurrent trip, low oil pressure) for post-incident analysis.

Applications

• Marine Genset Protection:
  • Primary protection for shipboard diesel/gas gensets, complying with SOLAS and IMO regulations. Prevents electrical faults from disrupting critical systems (navigation, communication) and protects gensets from damage in harsh marine environments.
• Industrial Backup Power:
  • Safeguards diesel gensets in data centers, hospitals, and manufacturing plants. Ensures reliable backup power by isolating faulty gensets and activating backups during outages.
• Power Generation Plants:
  • Protects small-scale generators (e.g., gas-fired microturbines) in distributed power systems, preventing cascading failures in grid-connected or islanded modes.
• Offshore Energy:
  • Used in offshore wind farms or oil rig power systems to protect backup gensets from electrical faults and environmental stressors (salt spray, vibration).

Availability and Support

• Condition: Available as new OEM (through DEIF A/S or authorized distributors) or genuine refurbished (via specialized suppliers like Marine Controls or Power Systems International).
• Warranty: 24-month warranty for new units (standard for DEIF products); refurbished units typically include a 12-month warranty.
• Documentation:
  • Technical datasheets, wiring diagrams, and configuration guides are accessible to DEIF customers via DEIF’s customer portal.
  • DEIF offers training and technical support for setup, calibration, and troubleshooting of GPU units.

Compatibility and Similar Products

• Compatible Systems:
  • DEIF Genset Controllers: DGC-2020, DGC-300, DGC-600.
  • DEIF Power Management Systems: PMS 300, PMS 400, PMS 600.
  • Third-party generators (Caterpillar, Cummins, MTU) and circuit breakers (ABB, Siemens) via standard protocols.
• Similar DEIF Products:
  • DEIF AGC-400: Generator controller with integrated basic protection functions (for small-scale applications where a standalone GPU is unnecessary).
  • DEIF RPU-300: Relay protection unit for low-voltage distribution networks (complementary to GPU for grid-level protection).

Installation and Maintenance Notes

1. Setup Requirements:
   • Mount in a control cabinet with proper ventilation (minimum 50 mm clearance) to avoid overheating. For marine applications, ensure compliance with shipboard electrical installation codes (e.g., IEC 60092).
   • Calibrate current/voltage inputs with CTs/VTs (current/voltage transformers) to match the generator’s rated output (critical for accurate fault detection).
2. Wiring Guidelines:
   • Use shielded cables for voltage/current signals to minimize EMI interference from generator alternators or starters.
   • For protection outputs (e.g., circuit breaker trip), use redundant wiring paths to ensure reliable fault isolation.
3. Safety & Troubleshooting:
   • Follow lockout-tagout (LOTO) procedures when wiring or servicing the GPU—incorrect configuration can disable critical protection functions.
   • Use LED indicators or the local HMI to diagnose status:
     • Green: Normal operation.
     • Red: Fault detected (protection action triggered).
     • Amber: Alarm (pre-fault condition, e.g., voltage deviation).
   • For persistent faults, verify CT/VT connections, check protection thresholds in DEIF PC-Tool, and inspect sensor inputs (e.g., oil pressure transducer).

Critical Notes

1. Model Variability: DEIF’s GPU series includes variants (e.g., GPU-100 for basic protection, GPU-200 for advanced marine applications). Confirm the exact model’s protection functions (e.g., LOE, reverse power) with DEIF to match your generator type.
2. CT/VT Compatibility: Ensure current transformers (CTs) and voltage transformers (VTs) are sized correctly for the GPU’s input range. Mismatched transformers will cause inaccurate measurements and delayed protection.
3. Genuine Parts Only: Use genuine DEIF GPU units for safety-critical applications. Aftermarket alternatives may not meet DEIF’s response time or marine/industrial certification standards, risking generator damage or safety hazards.