Why This Matters to North American Projects

For utilities, EPC contractors, developers, and electrical distributors in North America, choosing a pad-mounted transformer is about more than capacity and price. Compliance, complete documentation, project approval, delivery reliability, and long-term operating safety all play a major role in the selection process.

WINLEY Electric’s three-phase liquid-filled pad-mounted distribution transformer is UL/cUL certified under File No. E536138. For North American customers, this provides a clear compliance reference when evaluating transformer options for utility distribution, renewable energy, commercial, industrial, and infrastructure projects.

Certified Range and Compliance Reference

According to the UL certificate, the product has been evaluated against applicable IEEE standards, including IEEE C57.12.00 and IEEE C57.12.28. The certified range covers three-phase liquid-filled pad-mounted distribution transformers with rated capacity up to 5000 kVA, high-voltage system ratings from 26.0 kV to 36.0 kV, low-voltage ratings from 0.1 kV to 1.5 kV, and either loop-feed or radial-feed configurations.

For North American projects, UL/cUL certification helps reduce uncertainty during technical review and procurement. It gives engineers, purchasing teams, and project stakeholders a recognized basis for checking whether the transformer design meets expected safety and performance requirements.

Product Design and Application Fit

WINLEY three-phase pad-mounted transformers are designed for outdoor installation and distribution applications. The transformer core, windings, high-voltage load switch, fuses, and auxiliary devices are integrated into a sealed enclosure.

Depending on project requirements, the transformer can be supplied with live-front or dead-front construction, and configured for loop-feed or radial-feed systems. This gives utilities, commercial projects, renewable energy sites, and industrial facilities more flexibility when matching the transformer to the distribution layout.

This is especially useful for projects with strict documentation and approval requirements, including utility distribution networks, solar and energy storage systems, data centers, industrial facilities, commercial developments, and transportation infrastructure.

Factory Testing and Buyer Confidence

Before shipment, WINLEY can carry out routine factory tests according to project requirements. These may include winding resistance test, insulation resistance test, voltage ratio test, applied voltage withstand test, induced over-voltage withstand test, no-load loss test, load loss test, short-circuit impedance test, and sealing test.

These tests help verify the transformer’s electrical performance, insulation condition, manufacturing quality, and readiness for delivery. For North American buyers, complete testing and certification documents can make communication more efficient from quotation and technical review through to final approval.

For customers, choosing a UL/cUL certified transformer provides clearer compliance support, a smoother technical review process, more complete submittal documentation, and greater confidence before procurement and installation.

Looking Ahead

WINLEY Electric will continue to expand its certified transformer portfolio and support customers with reliable design, manufacturing, testing, and export services. Our goal is to help North American customers choose transformers with greater confidence, supported by clear documentation and dependable product support throughout the project.

For more information about WINLEY three-phase pad-mounted transformers, UL/cUL certification documents, or project-specific configuration support, please contact our sales and technical team.