| Brand | ROCKWILL |
| Model NO. | 20kV Three Phase Oil-Immersed Earthing Transformer |
| Rated voltage | 20kV |
| Rated capacity | 100kVA |
| Phases | Three-phase |
| Series | JDS |
Product Overview
Rockwill's JDS series oil-immersed earthing transformers provide reliable neutral grounding solutions for 20kV power systems. Designed with robust copper windings and advanced oil-cooling technology, these transformers ensure stable system operation while preventing damage from ground faults.
Basic Info
Key Specifications
Model: JDS-100/20
Capacity: 100kVA
Voltage: 20kV
Frequency: 50/60Hz
Winding: Copper two-winding design
Core: Ring-shaped silicon steel
Cooling: ONAN (Oil Natural Air Natural)
Impedance: Low zero-sequence impedance (<10Ω)
Certification: ISO 9001, CTQC tested
Technical Advantages
Superior Grounding Performance
Specially designed winding configuration for optimal neutral point stability
Withstands 100A short-circuit current for 10 seconds
Low zero-sequence impedance ensures effective fault current diversion
Advanced Oil-Cooled Design
Hermetically sealed corrugated tank prevents oil contamination
Mineral oil insulation with -30°C to +40°C operating range
Optional Midel 7131 ester fluid for enhanced fire safety
Robust Construction
Heavy-gauge steel tank with anti-corrosion treatment
Precision-engineered core with reduced magnetic losses
Vibration-resistant mounting system
Smart Protection Features
Standard Buchholz relay for internal fault detection
Pressure relief device for overload conditions
Oil level indicator with alarm contacts
Application Scenarios
Industrial Power Systems
Ideal for manufacturing plants with sensitive equipment
Protects against ground faults in 20kV distribution networks
Suitable for harsh industrial environments
Renewable Energy Installations
Wind farm collector substations
Solar park step-up stations
Biomass power generation facilities
Infrastructure Projects
Metro power supply systems
Airport electrical networks
Hospital backup power systems
Why Choose Rockwill?
20+ years of transformer manufacturing expertise
Custom engineering support available
Complete type test reports provided
Global service network with 24/7 technical support
Environmentally conscious production processes
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