| Brand | ROCKWILL |
| Model NO. | 33kv Oil Immersed Grounding /Earthing Transformer |
| Rated voltage | 33kV |
| Phases | Three-phase |
| Frequency range | 50/60Hz |
| Series | JDS |
Product Overview
Rockwill specializes in the design and manufacturing of 33kV oil immersed grounding transformers, engineered for reliable grounding protection in power systems. Our products comply with IEC and IEEE international standards, ensuring stable and safe operation of electrical networks.
Key Specifications
Product Highlights
Premium Core
The transformer core is made of high-quality cold-rolled oriented silicon steel sheets with 45° full diagonal joints. The iron yoke is securely clamped with through bolts, and the core columns are tied with fiberglass tape. The core surface is coated with silicone resin adhesive for moisture protection and noise reduction.
Superior Winding
The windings are constructed with high-quality copper conductors in a segmented cylindrical structure to enhance interlayer insulation. Vacuum drying technology is applied to ensure excellent electrical performance, high mechanical strength, and minimal partial discharge.
Advanced Insulation and Cooling
The oil immersed grounding transformer features a fully sealed tank with corrugated fins for efficient heat dissipation, eliminating the need for an oil storage tank. Oil tanks are sealed with oil-resistant rubber strips to prevent contact with air, preserving the insulating oil quality and extending transformer lifespan. Compact footprint, aesthetic appearance, and maintenance-free design are key benefits.
Comprehensive Protection Devices
Equipped with pressure relief valves, gas relays, and oil level gauges for real-time monitoring of oil condition. Temperature control devices support remote transmission, allowing convenient supervision of transformer operating temperature.
Technical Parameters
Transformer Type: Oil Immersed
Connection Groups: ZN (Zigzag)
Rated Voltage: Up to 36kV
Rated Current: Up to 3000A
Short Time Duration: 10s / 30s / 60s or customized
Cooling Method: ONAN, ONAF, AN, AF
Installation: Indoor / Outdoor
Ambient Temperature Range: -40°C to +40°C
Standards Compliance: IEC 60076-6, IEC 60076-1, IEEE
Enclosure Options: Transformer cabinet with customizable IP ratings, optional CT, VT, and isolation switch
Notes
Neutral short time current I0 = IG
Neutral zero-sequence impedance Z0 = Phase impedance / 3
±5% off-load tap changer
Confirm Z0 value before production if not self-limiting
Z0 tolerance ≤ 10%
Rockwill 33kV Oil Immersed Grounding Transformers combine advanced engineering and strict quality control to deliver dependable grounding solutions for power networks worldwide. For inquiries and customization, please contact us.
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