Pad-mounted transformer – safe, reliable, quiet, and efficient, the preferred solution for urban power distribution.
01 General
1.1 Project Description
This 750 kVA Pad mounted transformer was delivered to America in 2024. The rated power of the transformer is 750 kVA, with the primary voltage 13.2GrdY/7.62 kV to secondary voltage 0.48GrdY/0.277 kV. The connection group is YNyn0, pad mounted transformer is quickly accepted because of its advantages of compact structure, convenient installation, flexible operation, safe and reliable, simple maintenance and so on.
Pad mounted transformer has the following advantages:
excellent performance: high performance level, the use of 10, 11 series or amorphous alloy series, low loss, low noise, strong short-circuit resistance.
Complete functions, simple and reliable: can cut off the load current, the full range of current protection, high voltage line entry mode is flexible (ring network, terminal), can achieve phase break (undervoltage protection), with the basic function of substation.
1.2 Technical Specification
750 kVA transformer specifications type and data sheet
| Delivered to | America |
| Year | 2024 |
| Type | Pad mounted transformer |
| Standard | IEEE C57.12.34 |
| Rated Power | 750KVA |
| Frequency | 60HZ |
| Phase | 3 |
| Feed | Loop |
| Front | Dead |
| Cooling Type | ONAN |
| Primary Voltage | 13.2GrdY/7.62 KV |
| Secondary Voltage | 0.48/0.277 KV |
| Winding Material | Aluminum |
| Angular displacement | YNyn0 |
| Impedance | 5±7.5% |
| Efficiency | 99.32% |
| Tap Changer | NLTC |
| Liquid insulant | Mineral oil |
| Tapping Range | ±2*2.5% |
| No Load Loss | 0.89KW |
| On Load Loss | 7.5KW |
| Accessories | Standard Configuration |
1.3 Drawings
750 kVA pad mounted transformer diagram drawing and size.
02 Manufacturing
2.1 Core
| The transformer made of flat coil iron core has a completely closed magnetic circuit without magnetic leakage. In terms of raw materials, SCOTECH adopts the world’s first-class high-quality oriented silicon steel sheet, which is extremely thin in thickness and has the characteristics of high magnetic induction and low iron loss, ensuring the high-quality performance of the iron core. In terms of structure, the flat coil core is symmetrically wound with different widths and layers, and the cross section is a symmetrical step approximately circular. When used in transformers, the coil can be wound directly on the iron core, thereby reducing the coil turn length. |  |
2.2 Winding
 | Low-voltage foil winding refers to the use of thin metal foil as a conductor material, through the parallel overlap of the way to wind. This method is usually used on the low voltage side of the transformer. Foil winding uses a large conductor surface area to reduce coil resistance and eddy current losses, especially in low-frequency applications. Foil winding uses a large conductor surface area to reduce coil resistance and eddy current losses, especially in low-frequency applications. The structure of foil winding is relatively compact, which can achieve higher electrical conductivity in a limited space, which is especially important for small transformers. The foil-wound structure can effectively suppress electromagnetic interference and reduce electromagnetic noise, thus improving the operation stability of the transformer. High-voltage wire winding refers to the use of circular or rectangular wires for winding, usually used in the high-voltage side of the transformer. High voltage wire winding using insulation material coated wire, can withstand higher voltage, with better insulation performance, suitable for high voltage working conditions. The wire-wound structure is relatively strong and can better resist the influence of the external environment, such as moisture and temperature fluctuations, extending the service life of the transformer. High voltage wire winding can be designed according to different sizes and shapes to meet the requirements of various electrical systems. |
2.3 Tank
| The oil tank is cut, punched and bent by laser numerical control equipment to ensure the processing accuracy. The surface of the box adopts anti-corrosion design and special spray painting treatment, which is suitable for a variety of harsh environments. The top of the box can be naturally drained, and the tilt Angle of the top cover is not less than 3°. |  |
2.4 Final Assembly
03 Testing
| No. | Test Item | Unit | Acceptance Values | Measured Values | Conclusion |
| 1 | Resistance Measurements | % | Maximum resistance unbalance rate≤5% | 2.55 | Pass |
| 2 | Ratio Tests | % | The deviation of voltage ratio on the principal tapping: ≤0.5% Connection symbol: YNyn0 | 0.02% ~ 0.04% | Pass |
| 3 | phase-relation tests | / | YNyn0 | YNyn0 | Pass |
| 4 | No-load losses and excitation current | % kW | t: 20℃ I0: provide measured value P0: provide measured value the tolerance for no load loss is +10% | 0.22 0.918 | Pass |
| 5 | Load losses impedance voltage and efficiency | % kW kW | t: 85℃ Z%: measured value Pk: measured value Pt: measured value the tolerance for impedance is ±7.5% the tolerance for total load loss is +6% Efficiency not less than 99.32% | 4.83 6.918 7.836 99.34 | Pass |
| 6 | Applied Voltage Test | kV | LV: 10kV 60s | No collapse of the test voltage occurs | Pass |
| 7 | Induced Voltage Withstand Test | kV | Applied voltage (KV): 0.995 Duration(s): 48 Frequency (HZ): 150 | No collapse of the test voltage occurs | Pass |
| 8 | Leakage Test | kPa | Applied pressure: 20kPA Duration: 12h | No leakage and no Damage | Pass |
| 9 | Insulation Resistance Measurement | GΩ | HV&LV to Ground: | 30.4 | / |
| 10 | Oil Dielectric Test | kV | ≥45 | 54.50 | Pass |
| 11 | Noise test | dB | 51-55 | 53.6 | Pass |
| 12 | Lightning impulse test | kV | full wave, Half wav | No collapse of the test voltage occurs | Pass |
04 Packing and Shipping
05 Site And Summary
The Three Phase Pad Mounted Transformer, with its high performance, reliability, and adaptability, is widely used in various power distribution scenarios, providing users with efficient, safe, and cost-effective power solutions. Whether in commercial, industrial, or public infrastructure applications, it helps customers achieve stable power supply and energy optimization. Choose the Three Phase Pad Mounted Transformer to bring stable and reliable power support to your projects and step into a new era of smart energy together.
