The Usune 500kVA cast resin dry type transformer is an oil-free power distribution unit that uses air for cooling and insulation. Its windings are fully encapsulated in high-temperature-resistant epoxy resin, completely eliminating safety hazards such as oil leaks, fires, and explosions. The unit features low partial discharge, minimal noise, and zero pollutant emissions, allowing for long-term, maintenance-free operation. It is suitable for various demanding indoor power applications and is widely used in power distribution systems for commercial buildings, hospitals, schools, industrial plants, and subways.
The 500kVA cast resin dry type transformer contains no insulating oil and utilizes Class H high-temperature-resistant casting materials. It will not catch fire, explode, or leak oil under abnormal conditions such as overloads or short circuits. Indoor installation does not require specialized fire safety facilities like oil pits or firewalls, effectively reducing civil engineering and auxiliary costs.
There is no risk of oil leakage or harmful gas emissions during operation, ensuring compliance with green building and environmental standards. It can be installed directly in enclosed spaces—such as sealed hospital equipment rooms or underground subway equipment chambers—without the need for waste oil recovery systems, offering excellent environmental adaptability.
Optimized core lamination and symmetrical winding structures significantly reduce electromagnetic vibration and operating noise. The vacuum casting process eliminates internal winding bubbles, effectively controlling partial discharge and preventing insulation aging, thereby ensuring stable, continuous operation for over 20 years.
High-grade grain-oriented silicon steel is used for the core, significantly reducing both no-load and load losses. Designed for scenarios requiring continuous 24-hour power supply—such as factories and commercial buildings—it significantly reduces long-term energy consumption, aligning with global energy-saving standards.
It features an integrated structure utilizing air insulation and natural air cooling, eliminating the need for periodic replacement, filtration, or testing of insulating oil. Routine maintenance is limited to simple dust removal and checking terminal connections, drastically reducing labor and material costs associated with ongoing operations and maintenance.
It operates reliably in ambient temperatures ranging from -20°C to +40°C, at altitudes up to 1,000 meters, and in relative humidity of ≤95% (non-condensing). The sealed cast windings resist dust, moisture, and mild corrosion, making the unit suitable for complex environments such as underground spaces, humid factory facilities, and medical cleanrooms.
Compared to oil-immersed transformers of the same capacity, this unit is smaller and lighter, requiring less space for power distribution. Its ease of transport, lifting, and on-site assembly effectively shortens the construction timeline for power distribution projects.
The Usune 500kVA cast resin dry type transformer operates on the principle of electromagnetic induction, achieving AC voltage conversion and power transmission through magnetic flux coupling between the primary and secondary windings. The core operational process is as follows:
1. Alternating current flowing through the primary winding generates an alternating magnetic flux within the iron core;
2. The alternating magnetic flux passes through the secondary winding, inducing an alternating electromotive force via electromagnetic induction;
3. Voltage transformation (step-up or step-down) and power transmission are achieved based on the fixed turns ratio between the primary and secondary windings.
Unlike oil-immersed transformers, this unit relies entirely on air as the medium for insulation and heat dissipation between the core and windings, containing no insulating oil. Heat is dissipated through natural convection or forced air cooling, enabling safe and stable voltage transformation within enclosed indoor environments.
| Item | Technical Parameter |
| Rated Capacity Range | 30～2500 kVA (custom 500 kVA standard model) |
| High Voltage Rated Voltage | 10kV / 10.5kV |
| Low Voltage Rated Voltage | 0.4kV |
| Rated Frequency | 50/60Hz dual-frequency compatible |
| Vector Group | Dyn11 |
| Impedance Voltage | 4%～6% (standard configuration 6%) |
| Item | Technical Parameter |
| Allowable Ambient Temperature | -20℃～+40℃ |
| Applicable Altitude | ≤1000m |
| Allowable Relative Humidity | ≤95% (no condensation) |
| Standard Installation Location | Indoor |
A medium-sized underground subway station in East China procured three Usune 500kVA cast resin dry type transformers to power station lighting, ventilation, and signal control systems. Subway environments are enclosed and humid with strict fire safety requirements; oil-immersed transformers pose safety risks in such settings. Since entering service three years ago, the equipment has demonstrated low noise levels and stable partial discharge performance without requiring frequent maintenance, fully meeting safety standards for underground rail transit operations.
A tertiary hospital replaced aging oil-immersed transformers with two Usune 500kVA dry-type transformers to power precision medical equipment such as CT and MRI scanners. These products eliminate fire and pollution risks and operate silently, ensuring a stable power supply for medical equipment; additionally, their maintenance-free nature significantly reduces the hospital's equipment management workload.
A1: Yes. The equipment utilizes vacuum epoxy resin casting to create a fully sealed winding structure, effectively resisting moisture, dust, and corrosion. It operates stably in environments with relative humidity up to 95% (non-condensing) and is widely suitable for subway equipment rooms, underground distribution rooms, and humid factory facilities. For environments with prolonged condensation, custom IP-rated enclosures are available to enhance water resistance.
A2: The equipment is essentially maintenance-free, requiring no replacement, filtration, or testing of insulating oil. Routine maintenance involves only cleaning dust from the windings with compressed air and checking terminal tightness every six months; no specialized testing equipment is needed, resulting in significant long-term operational cost savings.
A3: The primary advantage is the absence of fire or explosion risks. Traditional oil-immersed transformers contain flammable insulating oil—making them prone to fire or explosion in the event of a short circuit or overheating—and require auxiliary facilities such as oil pits and firewalls. Usune cast-resin dry-type transformers utilize flame-retardant solid resin and contain no combustible media; they do not propagate fire in the event of a fault and can be installed directly in densely populated indoor locations—such as hospitals, schools, and shopping malls—without the need for additional fire-safety infrastructure.
Address
No. 298, Wei 17th Road, Yueqing Economic Development Zone, Yueqing, Wenzhou City, Zhejiang Province, China
Tel
