Reliable Power, Compact Design - Your Trusted Pad-Mounted Distribution Transformer
01 General
1.1 Project Description
Delivered to the USA in 2024, this 2000 kVA three-phase pad-mounted distribution transformers is built to comply with IEEE Std C57.12.34-2022 and aligns with DOE 2016 energy efficiency regulations. The transformer features a 4.16 kV primary and a 480GrdY/277 V secondary with a Dyn1 vector group. It uses copper windings for reliable performance and durability, KNAN cooling for efficient heat dissipation, and FR3 natural ester fluid for improved fire safety and environmental sustainability.
The design features a loop feed system and dead-front access, supporting both safe operation and installation flexibility. It also includes a no-load tap changer with a ±2 × 2.5% voltage regulation range. With an impedance of 5.75%, no-load loss of 1.350 kW, and load loss of 16.000 kW, this transformer delivers efficient and stable power conversion for medium-voltage distribution systems.
Designed to meet the demands of today’s utility and industrial settings, our pad-mounted distribution transformers offer a compact, low-profile design without compromising on safety or long-term durability.
1.2 Technical Specification
2000kVA three phase pad mounted transformer specification and data sheet
| Delivered to | USA |
| Year | 2024 |
| Type | Three phase pad mount transformer |
| Standard | IEEE Std C57.12.34-2022 |
| Rated Power | 2000KVA |
| Frequency | 60HZ |
| Feed | Loop |
| Front | Dead |
| Phase | three |
| Cooling Type | KNAN |
| Liquid insulant | FR3 Oil |
| Primary Voltage | 4.16 Kv |
| Secondary Voltage | 0.48 Kv |
| Vector Group | Dyn1 |
| Winding Material | Copper |
| Impedance | 5.75% |
| Efficiency and Losses Standard | DOE 2016 |
| Tap Changer | NLTC |
| Tapping Range | ±2*2.5% |
| No Load Loss | 1.350 kW |
| On Load Loss | 16.000 kW |
| Accessories | Standard Configuration |
1.3 Drawings
2000kVA three phase pad mounted transformer dimensions and weight details
02 Manufacturing
2.1 Core
| As a critical magnetic path, the transformer core transfers flux between primary and secondary windings. SCOTECH cores use silicon steel laminations with excellent permeability, enabling low losses under high flux density. Carefully selected materials ensure stable magnetic response and long-term efficiency across varying loads. |  |
2.2 Winding
Designed for 4.16 kV networks, this 2000 kVA Dyn1 transformer uses copper windings. HV coils adopt a multi-layer helical structure with paper-covered wire for superior insulation. LV foil winding enhances mechanical strength, heat dissipation, and system reliability under continuous load.
2.3 Tank
| The transformer tank is hermetically sealed to block air and moisture, protecting the insulating oil from oxidation and contamination. This improves oil life, maintains dielectric strength, and ensures long-term stability of internal components. |  |
2.4 600A T-Connector HV Bushings
 | The 600A integral bushing suits 4.16kV systems with ~277A load. It delivers stable performance with reliable insulation and conductivity for long-term use. Connected via a T-type cable connector, one side links to the power cable while the other connects to an elbow-type surge arrester, providing effective overvoltage and lightning protection.
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2.5 Final assembly
 | The core and windings are assembled, aligned, and secured with proper insulation supports. Lead wires are arranged and connected to the bushings for later welding. The cleaned tank is prepared for assembly. The active part is lifted into the tank, positioned accurately, grounding is secured, and bottom supports are adjusted to ensure stability and insulation. |
03 Testing
Routine Test and Testing Standard
1. Resistance Measurements according to IEEE C57.12.90-2021 Clause 5
2. Phase-relation Test according to IEEE C57.12.90-2021 Clause 6
3. Ratio Tests according to IEEE C57.12.90-2021 Clause 7
4. No Load Losses and No Load Current according to IEEE C57.12.90-2021 Clause 8
5. Load Losses, Impedance Voltage and Efficiency according to IEEE C57.12.90-2021 Clause 9
6. Induced Voltage Withstand Test according to IEEE C57.12.90-2021 Clause 10.5.1
7. Applied Voltage Test according to IEEE C57.12.90-2021 Clause 10.6
8. Leak Testing with Pressure for Liquid Immersed Transformers – the leaking test at 15 kPa shall be conducted for 12 h without leakage. No permanent deformation.
9. Insulation Resistance Measurement
10. Oil Dielectric Test
Test Result
| No. | Test Item | Unit
| Acceptance Values | Measured Values | Conclusion |
| 1 | Resistance Measurements | % | Maximum resistance unbalance rate | 0.453 | Pass
|
| 2 | Ratio Tests | % | The deviation of voltage ratio on the principal tapping: ≤0.5% Connection symbol: Dyn1 | 0.05%-0.10% | Pass
|
| 3 | phase-relation tests | / | Dyn1 | Dyn1 | Pass
|
| 4 | No-load losses and excitation current | % kW | I0 :: provide measured value P0: provide measured value the tolerance for no load loss is +0% | 0.10% 1.390 | 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 +0% Efficiency not less than 99.51% | 5.62% 15.032 16.422 99.52% | Pass
|
| 6 | Applied Voltage Test | kV | HV: 40kV 60s LV: 10kV 60s | No collapse of the test voltage occurs | Pass
|
| 7 | Induced Voltage Withstand Test | kV | Applied voltage (KV): 0.960 Duration(s):40 Frequency (HZ): 180 | No collapse of the test voltage occurs | Pass
|
| 8 | Leakage Test | kPa | Applied pressure：50kPA Duration：12h | No leakage and no Damage | Pass
|
| 9 | Insulation Resistance Measurement | GΩ | HV-LV to Ground: LV-HV to Ground: HV&LV to Ground: | 2.66 3.25 3.72 | / |
| 10 | Oil Dielectric Test | kV | ≥40 | 53.6 | Pass
|
04 Packing and Shipping
05 Site And Summary
Scotech’s 2000 kVA three-phase pad mounted distribution transformer is built with careful craftsmanship and strict quality checks to ensure dependable, efficient, and safe power conversion for medium-voltage systems. Manufactured with precision-stacked cores, foil-wound LV coils, and paper-insulated copper HV windings, it ensures low noise, strong insulation, and long-term durability. The robust steel tank protects internal components against shocks and vibrations, while integrated Bay-O-Net fuses and IEEE 386-compliant MOV elbow surge arresters provide enhanced system protection.
Designed to meet IEEE Std C57.12.34-2022 and DOE 2016 efficiency standards, this pad mounted distribution transformer offers a compact, low-profile solution ideal for utility and industrial use. At Scotech, we are committed to delivering top-quality pad mounted distribution transformers that prioritize safety, performance, and environmental sustainability – powering your operations with confidence.
