4000 kVA Cast Resin Dry Type Transformer

4000 kVA Cast Resin Dry Type Transformer is prepared for indoor cast-resin transformer duty. It covers 10kV / 11kV / 13.8kV / 33kV input networks and 400V / 690V / 3.3kV output distribution. It uses AN (Base) / AF (Forced Air) cooling or thermal design data where specified. This series description presents the application, construction, protection, and specification details in finished product copy.

Selecting the Right Dielectric Architecture

For indoor cast-resin transformer duty, selecting the Right Dielectric Architecture is treated as a practical design and selection point rather than generic catalog wording.

• The 4000 kVA Dry Type Transformer represents a significant capital investment for large-scale infrastructure. At this 4 MVA capacity level, the equipment serves as a primary substation node. Consequently, selecting the correct insulation technology is critical for long-term reliability.
• As a comprehensive manufacturer, we engineer this dry distribution transformer in two distinct dielectric architectures: Vacuum Pressure Impregnated (VPI) and Cast Resin (CRT). The choice between these two depends entirely on the specific environmental conditions and maintenance philosophy of the installation site.

Option A: Cast Resin (Epoxy Technology)

For indoor cast-resin transformer duty, option A: Cast Resin (Epoxy Technology) is treated as a practical design and selection point rather than generic catalog wording.

• For environments with high humidity, conductive dust, or strict fire codes, we recommend the cast resin type transformer.
• Encapsulation Physics: In this design, the high-voltage windings are completely vacuum-encapsulated in a solid block of silica-filled epoxy. 1 This creates a hermetic seal around the conductors.
• The Advantage: This epoxy resin dry type transformer offers the highest level of environmental protection (E2/C2/F1 Class). It is impervious to moisture absorption during shutdowns and can withstand "Pollution Degree 3" environments (heavy industrial grime) without flashover, as there is no exposed creepage path on the coil surface.

Option B: VPI (Vacuum Pressure Impregnated)

For indoor cast-resin transformer duty, option B: VPI (Vacuum Pressure Impregnated) is treated as a practical design and selection point rather than generic catalog wording.

• For controlled indoor environments where weight and airflow are priorities, the vpi transformer is the superior engineering choice.
• Open-Wound Physics: Instead of a solid block, VPI coils are wound with porous Nomex® or Aramid paper and then pressure-cycled with high-temperature polyester varnish. This leaves the coil "open" to the air.
• Thermal Recovery: With the conductors directly exposed to cooling air (rather than buried in resin), VPI units dissipate heat faster and recover more quickly from overload spikes.
• Weight Reduction: Eliminating the heavy epoxy mass reduces the total unit weight by approximately 15-20%, lowering structural loading requirements for mezzanine or rooftop installations.

Connection Engineering: The 5700A Challenge

For indoor cast-resin transformer duty, connection Engineering: The 5700A Challenge is treated as a practical design and selection point rather than generic catalog wording.

• At 4000 kVA, the low-voltage output current at 400V reaches a massive ~5773 Amps. This renders standard cable connections physically dangerous due to magnetic repulsion forces.
• Busduct Interface: Regardless of whether you choose VPI or Cast Resin, the 4 MVA units feature a specialized Full-Flange Throat. This is precision-machined to mate directly with Copper Busbar Trunking systems, ensuring that the mechanical stress from the heavy busbars is transferred to the enclosure frame, not the transformer bushings.

Technical Data Sheet

Technical Data Sheet provides selection data that helps compare ratings, voltage classes, and installation requirements.

• Technical Parameter.
• Specification / Options.
• 10kV / 11kV / 13.8kV / 33kV.
• 400V / 690V / 3.3kV.
• ~5773 A (at 400V) / ~3347 A (at 690V).
• Technology Options.

Typical Application Context

Typical Application Context connects the product rating with the field conditions, enclosure layout, and distribution role it is normally selected for.

• 4000 kVA cast resin dry type transformer installed in a chemical.
• Cast Resin Applications: Underground metro stations, chemical plants, and humid tropical regions where moisture resistance is non-negotiable.
• VPI Applications: Marine vessels (for lighter weight), cleanroom data centers, and retrofits in buildings with limited elevator weight capacity.

Electrical and Mechanical Data

The table data is organized for quick rating comparison, project specification, and transformer selection.

Product Detail Images