Three Phase Pad Mounted Transformer: Powering Progress, Securely Enclosed.
01 General
1.1 Project Description
750 kVA pad mounted transformer in front yard was delivered to America in 2024. The rated power of the transformer is 750 kVA with KNAN cooling. The high voltage is 34.5GRDY/19.92 kV with ±2*2.5% tapping range (NLTC), the low voltage is 0.48GrdY/0.277 kV, they formed a vector group of YNyn0.
A three-phase pad-mounted transformer is a fully enclosed, ground-level electrical device that serves as a critical interface in the distribution network, reliably stepping down medium-voltage electricity from utility lines to lower voltages suitable for end consumers. Encased in a locked, tamper-resistant steel cabinet, it is designed for safe, durable, and low-profile outdoor installation in residential, commercial, and industrial areas, providing power to multi-unit buildings, shopping centers, and factories where three-phase service is required. Its primary advantages include enhanced public safety, protection against environmental elements, and facilitated maintenance, making it an indispensable and ubiquitous component of the modern electrical infrastructure.
1.2 Technical Specification
750 kVA pad mounted transformer in front yard specifications type and data sheet
| Delivered to | USA |
| Year | 2024 |
| Type | Pad mounted transformer |
| Standard | IEEE C57.12.00 |
| Rated Power | 750 kVA |
| Frequency | 60HZ |
| Phase | 3 |
| Feed | Loop |
| Front | Dead |
| Cooling Type | ONAN |
| Primary Voltage | 34.5GRDY/19.92 kV |
| Secondary Voltage | 0.48GrdY/0.277 kV |
| Winding Material | Aluminum |
| Angular displacement | YNyn0 |
| Impedance | 5.75% |
| Efficiency | 99.2% |
| Tap Changer | NLTC |
| Tapping Range | ±2*2.5% |
| No Load Loss | 1.3 kW |
| On Load Loss | 7.64 kW |
1.3 Drawings
750 kVA pad mounted transformer in front yard diagram drawing and size.
02 Manufacturing
2.1 Core
Featuring a compact three-legged core assembly, this transformer’s core is built with stacked laminations of silicon steel to minimize eddy current losses. The windings for all three phases are symmetrically wound on the three vertical core legs, which are interconnected by top and bottom yokes. This robust design ensures efficient magnetic flux linkage and structural integrity within the confined enclosure.
2.2 Winding
 | The winding design employs a rectangular aluminum foil for the LV section, offering high capacitance and radial strength against fault currents. The complementary HV winding uses layered copper wire, providing the necessary flexibility for precise insulation control and compact, reliable operation within the pad-mounted enclosure. |
2.3 Tank
Constructed from welded steel plates, the tank provides mechanical protection and environmental containment for the internal components. It features a compact shape with corrugated fins for passive heat exchange, ensuring reliable thermal management and a long service life at the installation site.
2.4 Final Assembly
In its fully assembled state, pad mounted transformer in front yard is a self-contained unit featuring the internally mounted core-coil assembly connected to the tap changer, submerged in coolant within a corrosion-resistant tank. The transformer is finished with vacuum pressure gauge, thermometer and other accessories, and a locked compartmentalized enclosure for secure underground cable connections.
03 Testing
A comprehensive test suite validates design and safety. It begins with core electrical checks like DC winding resistance, insulation resistance, and vector group confirmation. Dielectric strength is proven via separate-source and induced AC withstand tests. Performance is verified by measuring no-load current, load loss, impedance, and efficiency, concluding with a pressure test to ensure a leak-proof tank.
04 Packing and Shipping
4.1 Packing
To package pad mounted transformer in front yard, start by laying a tin foil bag on its tray, covering the transformer with the bag, and putting desiccant inside. Seal the bag except for one opening, extract the gas with a vacuum cleaner, and then seal the opening with a sealing machine. After that, attach corner protectors (foam, plastic or cardboard type) around the transformer and wrap it with protective film. Ultimately, enclose it in an outer wooden crate, which has forklift markings and center of gravity markings sprayed on.
4.2 Shipping
Shipping involves initial road transport via heavy-duty truck to the export port. After being containerized for protection, it is shipped across the ocean. This efficient two-stage process leverages the security of containerization for the international sea voyage, ensuring safe and reliable delivery to the United States.
05 Site And Summary
In summary, this pad mounted transformer in front yard delivers a robust combination of performance, durability, and low life-cycle cost. It is a complete solution designed to meet the rigorous demands of today’s utility applications. Choose our product as your trusted partner for building a smarter, more reliable electrical infrastructure.
