Epoxy resin insulated dry-type transformers manufactured by our company are developed based on advanced domestic and international technologies.We have independently developed the SC(B)12~SC(B)18 series of filler-reinforced thin-insulation cast resin dry-type transformers.

The series features high-quality materials and scientifically optimized formulations,and is manufactured using advanced manufacturing and testing equipment under strict quality control processes.

The transformers offer high reliability and long service life.Depending on installation requirements,enclosures with various protection ratings(IP levels)are available,or the unit may be supplied without enclosure.

These transformers are widely used in power transmission and distribution systems and are particularly suitable for high-rise buildings,commercial centers,airports,tunnels,chemical plants,nuclear power stations,ships,and other critical or special environments.

• The windings are fully encapsulated in epoxy resin,providing flame-retardant,fire-resistant,and explosion-resistant performance.The transformer is maintenance-free,environmentally friendly,compact in size,and suitable for direct installation at load centers.
• An optimized design and precision casting process ensure low partial discharge levels,low operating noise,high mechanical strength,excellent short-circuit withstand capability,and superior heat dissipation performance.Under Forced Air cooling(AF)conditions,the transformer capacity can be increased by up to 50%.
• Equipped with an intelligent temperature controller,the transformer features fault alarm,over-temperature alarm,over-temperature trip,and data logging functions.
• Through an RS485 serial communication interface,the system can be connected to a computer or supervisory platform for centralized monitoring and control.　

Iron Core

The core is constructed from high-quality cold-rolled grain-oriented(CRGO)silicon steel laminations with a fully mitered 5-step lap joint design to minimize magnetic flux distortion.

Core limbs are tightly bound with Class H glass-fiber adhesive tape,and the core surface is sealed with insulating resin to provide moisture and corrosion protection.This design effectively reduces no-load losses,excitation current,and core noise.

The upper yoke surface is coated with self-leveling paint for a smooth and refined finish.Clamping components are fabricated using laser cutting and CNC bending processes,followed by acid pickling and powder coating,ensuring uniform weld seams,structural strength,and high-quality appearance.

Low-Voltage Winding

The low-voltage winding adopts a foil-type structure,effectively eliminating axial spiral angle deviations associated with conventional wire winding and ensuring balanced ampere-turn distribution.

Axial cooling ducts are incorporated within the coil to enhance heat dissipation performance.Interlayer insulation utilizes DMD epoxy resin pre-impregnated material,and the winding is integrally cured to form a solid and mechanically robust structure.

High-Voltage Winding

The winding is manufactured on a high-precision winding machine.For large-capacity winding,an arbor is used.The inner and outer walls of the winding are wrapped with high-strength polyester film.The high-voltage winding adopts a“self-leveling”structure to form a“mirror-like”surface,ensuring a smooth coil end and consistent height.It effectively improves the ability to withstand short-circuits,and the coil will never crack.

Manufacturing process

The resin compound is processed using advanced mixing techniques combined with vacuum film degassing technology,ensuring uniform mixing and elimination of entrapped air bubbles.The coils are cast under vacuum pressure,and the resin insulation provides full encapsulation with thorough impregnation between layers and turns.

The partial discharge level of the product is controlled to below 5 pC.The cast body exhibits a dense,void-free cured structure with excellent flame-retardant and explosion-resistant properties,and it is non-toxic and environmentally benign.These advanced manufacturing transformers ensure product quality and high operational reliability.

Temperature monitoring and control system

1.The temperature controller utilizes PT100 resistance temperature detectors(RTDs)to acquire transformer temperature signals.The intelligent controller unit continuously monitors the winding temperature,ensuring stable operation and improved system reliability.

2.The anti-interference performance complies with the requirement of JB/T 7631 Resistance Thermometers for Transformers.

3.Temperature controllers with optional functions,including computer communication interfaces,are available upon request.

4.The unit is designed for embedded installation.For enclosed transformers,the controller can be directly mounted on the enclosure panel;for non-enclosed units,it can be installed on the transformer body or on a safety barrier.This design is compact,practical and easy to install.

5.The standard panel cut-out dimensions for commonly used temperature controllers is 152×76 mm(L×W).

Forced air cooling system

1.Dry-type transformers are available with two cooling methods:Natural Air cooling(AN)and Forced Air cooling(AF).

2.Under Natural Air cooling(AN),the transformer is capable of continuously delivering 100%of its rated capacity under normal operating conditions.

3.Under Forced Air cooling(AF),cross-flow top-mounted cooling fans are employed.This cooling fans feature low noise,high airflow pressure,and an aesthetically design.Under normal operating conditions,the transformer can deliver up to 150%of its rated capacity.This configuration is suitable for emergency overload and intermittent overload operation.However,due to the increased load losses and impendence voltage rise overload conditions,long-term conditions overload operation under Forced Air cooling(AF)is not recommended.

4.For both Natural Air(AN)and Forced Air(AF)cooled transformers,good ventilation of the transformer room must be ensured.When the transformer is installed in a basement or other areas with limited ventilation,supplementary ventilation and heat dissipation equipment should be provided to ensure optimal cooling performance.The required ventilation volume should be selected based on 3–4 m³/min per 1 kW of total losses(P₀+Pk).

5.The number of cooling fans,fan power ratings,and power supply configurations for transformers of standard capacities are listed in the table below:

变压器容量:Rated Capacity

风机数量×功率:Fan Quantity×Rated Power

风机电源:Fan Power Supply

Protective Enclosure

The protective enclosure provides enhanced safety protection for the transformer.Protection levels such as TP20 and IP23 are available to meet different application requirements.Enclosure materials,including cold-rolled steel plate and stainless steel,are available for customer selection.

Terminal Arrangement

The transformer can be manufactured with conventional cable connections,standard enclosed busbar systems,or standard side cable outlets to accommodate different interface requirements.Special side outlets and other customized connection arrangements can also be designed upon customer request.

进出线方式图：Cable Entry and Exit Arrangement Diagram

低压电缆上出线：Low-Voltage Top Cable Entry

低压电缆下出线：Low-Voltage Bottom Cable Entry

高压电缆上出线：High-Voltage Top Cable Entry

高压电缆下进线：High-Voltage Bottom Cable Entry

电缆卡：Cable Clamp

电缆支架：Cable Support Bracket

风机：Cooling Fan