air-type transformer
1. Ultra-high energy efficiency: even greater energy savings during long-term operation.
2. Safety: oil-free, made of epoxy resin, fire-resistant and explosion-proof, can be installed indoors and in distribution panels.
3. High reliability: high short-circuit resistance, low partial discharge, stable insulation performance.
4. Ultra-low noise: optimized iron core, low noise level, suitable for hospitals, schools, and residential areas.
5. Maintenance-free: moisture-proof, dust-proof, and anti-pollution, no oil replacement required, longer service life.
I. Product Definition and Applicable Standards
TransformerEpoxy cast SCB made of dry alloy is a three-phase distribution transformer with ultra-low losses, featuring 12 cores. It further reduces no-load and load losses, improves noise performance and short-circuit withstand capability, while maintaining an oil-free, high fire resistance, and explosion-proof design.
Applicable standards:
IEC 60076 series
Insulation Class: Class F (maximum operating temperature 155℃)
Fire resistance complies with GB/T 14598.13, fire resistance class FV0, non-flammable, no toxic fumes emitted.
Oil-free design completely eliminates oil leakage and fire risk.
II. Key Technical Parameters (Customizable)
Element |
Standard Specification |
Notes |
Rated voltage (HV/LV) |
High voltage: 35 kV, tap range ±2×2.5% Low voltage: 0.4 kV (three-phase four-wire) |
Customizable range 0.69 kV/1.14 kV; tap changer operates only when power is off. |
Rated capacity |
Standard power: 30 kVA–2500 kVA, up to 3150 kVA |
100, 200, 400, 630, 1000, 1600, 2000 kVA |
Connection Group |
Dyn11 (default) |
High-voltage delta connection, low-voltage star connection with neutral; suitable for grounding and relay protection. |
Cooling Mode |
AN / AF |
AN: 120% continuous load; AF: 150% continuous load |
Insulation and temperature rise |
Class F; winding 100 kΩ, core 80 kΩ. |
Vacuum casting + fiberglass; PD ≤10 pC |
Protection degree |
Standard IP20, IP30/IP40 optional. |
IP20: for clean room use; IP40: for outdoor / heavy dust use |
Environmental conditions |
Altitude ≤1000 m; temperature from -5℃ to +40℃; humidity ≤95%. |
Thermal insulation reduced for high-altitude use; frost-resistant construction optional. |
III. Design Features
Main system
High-permeability grain-oriented cold-rolled silicon steel (0.30–0.35 mm), 45° stepped lap joint.
Epoxy coating for moisture and rust protection. Secured with non-magnetic fastening straps, low vibration. Noise level: 2–3 dB(A) lower than SCB11, typically ≤52 dB(A).
Winding technology
Low-voltage winding: high-precision copper foil; high-voltage winding: oxygen-free copper conductor.
Vacuum epoxy casting with fiberglass reinforcement, bubble-free and void-free, extremely high mechanical strength. Uniform current distribution, low eddy current losses. Excellent short-circuit and lightning overvoltage resistance.
Temperature control and monitoring
Electrostatically sprayed cold-rolled steel, optimized ventilation louvers.
Protection rating IP30/IP40, moisture and dust-proof design. Removable housing for easy maintenance. Copper terminals with low contact resistance and reliable connection.
Tap changer device and wiring
Off-circuit tap changer on the high-voltage side with stable contact.
Low-voltage copper terminals for simplified wiring installation and capacity expansion.
IV. Main Performance Advantages
Enhanced energy efficiency
High efficiency and energy saving
With an annual consumption frequency of 8000 hours and a 70% load, a 1000 kVA unit saves approximately 500 kWh per year compared to SCB11.
Ultra-safe and environmentally friendly
Oil-free, flame-retardant (flame retardancy class FV0), emits no toxic gases.
Can be installed directly in building power consumption centers (high-rise buildings, hospitals, subways) without oil separation pits or fire barriers.
High environmental adaptability
Fully sealed design: waterproof, dustproof, resistant to salt spray, prevents condensation.
Stable in coastal, high-humidity, and heavily polluted industrial environments. No pre-drying required after prolonged shutdown.
High reliability and maintenance-free.
Partial discharge ≤10 pC, slow insulation aging.
V. Typical Application Areas
Power grids: 35 kV substations, reconstruction of urban/rural networks, step-down substations in industrial parks.
Public buildings: offices, shopping malls, airports, subways, hospitals, schools.
Hazardous industries: chemical plants, coal mines, oil refineries, pharmaceutical facilities.
Coastal areas and high-humidity regions
New energy sources: step-up substations for small and medium-sized solar/wind power stations.
