| Brand | ROCKWILL |
| Model NO. | 66kV Three Phase Oil-Immersed Earthing Transformer |
| Rated voltage | 66kV |
| Phases | Three-phase |
| Series | JDS |
Product Overview
Rockwill delivers reliable and high-performance earthing transformers designed for 66kV power systems. Our oil-immersed transformers are engineered to provide stable neutral grounding solutions while ensuring operational safety and system protection. Manufactured in compliance with international standards including IEC and GB, these transformers incorporate premium materials and rigorous quality control throughout production.
Basic Info.
Key Features
Voltage Class: 66kV system voltage (200 BIL)
Capacity Range: Standard units from 100kVA to 10,000kVA
Winding Configuration: Optimized zigzag (ZNyn) design
Cooling System: ONAN/OFAF cooling options
Insulation: Mineral oil or synthetic ester fluid
Construction:
Corrugated tank or radiator cooling
Hermetically sealed or conservator tank options
CRGO silicon steel core
Copper/aluminum windings
Technical Advantages
Enhanced Safety: Built-in Buchholz relay and pressure relief device
Low Impedance: Zero-sequence impedance <15Ω for effective fault current management
Durability: Corrosion-resistant paint system for outdoor installations
Efficiency: Reduced no-load losses through optimized core design
Flexibility: Off-circuit tap changer (±5% in 2.5% steps)
Typical Applications
Utility Networks:
Neutral grounding for 66kV transmission systems
Arc suppression coil connections
Resistance grounding systems
Industrial Plants:
Petrochemical facilities
Mining operations
Steel manufacturing plants
Renewable Energy:
Wind farm collector stations
Solar PV substations
Hydroelectric plants
Performance Specifications
Temperature Range: -30°C to +40°C ambient
Humidity: ≤95% monthly average
Altitude: Up to 2000m ASL
Sound Level: ≤75dB at 1m
Efficiency: ≥99.2% at full load
Testing Protocol
All units undergo comprehensive testing including:
Zero sequence impedance measurement
Induced overvoltage test (260Hz)
Lightning impulse test (350kV)
Temperature rise test (65K max.)
Oil dielectric strength test (≥50kV)
Service Conditions
Suitable for indoor/outdoor installation
Wind resistant up to 35m/s
Non-explosive environments
Seismic capability: 0.3g horizontal acceleration
