01 General
1.1 Project Description
Project Spotlight When our Canadian client approached us, they needed transformers that could handle harsh climates, heavy loads, and continuous operation. That’s exactly what we delivered: two 2500 kVA pad-mounted transformers designed to provide reliable, consistent power for industrial and commercial networks. These units aren’t just machines-they’re a promise. A promise that energy will keep flowing, safely and efficiently, day after day.
1.2 Technical Specification
2500kVA three phase pad mounted transformer specification and data sheet
| Delivered to | Canada |
| Year | 2025 |
| Type | Three phase pad mount transformer |
| Standard | CSA C227.4:21 |
| Rated Power | 2500KVA |
| Frequency | 60HZ |
| Feed | Loop |
| Front | Dead |
| Phase | three |
| Cooling Type | ONAN |
| Liquid insulant | Mineral Oil |
| Primary Voltage | 25 Kv |
| Secondary Voltage | 0.6 Kv |
| Vector Group | Dyn1 |
| Winding Material | Aluminum |
| Impedance | 5.75% |
| Tap Changer | NLTC |
| Tapping Range | ±2*2.5% |
| No Load Loss | 2500 W |
| On Load Loss | 24000 W |
| Accessories | Standard Configuration |
1.3 Drawings
2500kVA three phase pad mounted transformer dimensions and weight details
02 Manufacturing
We designed these 2500 kVA three phase pad mounted transformers specifically for Canada’s challenging outdoor conditions. With aluminum windings and ONAN oil cooling, they stay stable even when the grid fluctuates or the temperature swings dramatically. The loop-feed dead-front design keeps people safe, while the Dyn1 vector group makes integrating into grounded neutral networks simple. Basically, we made sure they’d perform reliably no matter what the weather throws at them-and keep operators confident while they’re at it.
2.1 Core
At the heart of each transformer is a compact, three-leg core that channels magnetic flux smoothly and efficiently. We used low-loss silicon steel sheets with corrosion-resistant treatment to reduce energy loss and noise. It’s a simple core, yes, but one we designed carefully to last and operate quietly, keeping your system stable under all kinds of loads.
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2.2 Winding
 | On the low-voltage side, we use foil windings with sturdy copper busbar leads. This means short circuits won’t faze them, and heat dissipates efficiently. The high-voltage side uses paper-insulated flat aluminum wire-compact, cost-effective, and reliable. Together, these winding choices give you the balance we’re always aiming for: durable, efficient, and ready for long-term outdoor operation. |
2.3 Protective Features
Safety was never an afterthought. We added a Bay-O-Net fuse and a current-limiting backup fuse for layered protection, while the no-load tap changer allows for ±2 × 2.5% voltage adjustments. That means when the grid conditions change, the transformers can adapt without skipping a beat. We like to think of them as smart, protective partners for your distribution network.
2.4 Tank
 | The 2500 kVA three phase pad mounted transformer tank itself is made from sealed mild steel, bolted for extra strength. Every surface is sandblasted, corners included, then coated with weather- and UV-resistant epoxy primers and topcoats. It’s tough enough to handle the Canadian sun, snow, and rain while keeping the internal components safe and maintaining excellent heat dissipation. You don’t have to worry about the elements-they’ve got it covered. |
2.5 Assembly
We carefully assemble the core and windings, connect the leads, install the tank and accessories, fill it with mineral oil, and seal it. Then we run it through a full suite of CSA-standard tests: resistance, ratio, phase-relation, losses, applied and induced voltage withstand, insulation resistance, dielectric strength, and leak testing. Honestly, we check everything twice. If it passes, you can trust it to perform reliably from day one. |  |
03 Testing
Routine Test and Testing Standard
CSA C227.4-21 Three-phase, pad-mounted distribution transformers with separable insulated high-voltage connectors
CSA-C802.1-13 (R2022) Minimum Efficiency Values for Liquid-Filled Distribution Transformers
- Resistance Measurements
- Ratio Tests
- Phase-relation Test
- No Load Losses and No Load Current
- Load Losses, Impedance Voltage and efficiency
- Applied Voltage Test
- Induced Voltage Withstand Test
- Leak Testing with Pressure for Liquid Immersed Transformers： The leaking test at 50KPa shall be conducted for 12h without leakage. No permanent deformation.
- Insulation Resistance Measurement
- Oil Dielectric Test
Test Results
| No. | Test Item | Unit | Acceptance Values | Measured Values | Conclusion |
| 1 | Resistance Measurements | % | Maximum resistance unbalance rate | 0.82 | Pass |
| 2 | Ratio Tests | % | The deviation of voltage ratio on the principal tapping: ≤0.5% | -0.06~-0.05 | Pass |
| 3 | phase-relation tests | / | Dyn1 | Dyn1 | Pass |
| 4 | No-load losses and excitation current | / | I0 :: provide measured value | 0.35% | Pass |
| P0: provide measured value | 2.214kW | ||||
| the tolerance for no load loss is +10% | / | ||||
| 5 | Load losses impedance voltage and efficiency | / | t:85℃ the tolerance for impedance is ±7.5% the tolerance for total load loss is +6% | / | Pass |
| Z%: measured value | 5.69% | ||||
| Pk: measured value | 22.183kW | ||||
| Pt: measured value | 24.397kW | ||||
| Efficiency not less than 99.37% | 99.43% | ||||
| 6 | Applied Voltage Test | kV | HV:50kV 60s LV: 10kV 60s | No collapse of the test voltage occurs | Pass |
| 7 | Induced Voltage Withstand Test | kV | Applied voltage (KV): 2 Ur | No collapse of the test voltage occurs | Pass |
| Duration(s):48 | |||||
| Frequency (HZ): 150 | |||||
| 8 | Leakage Test | kPa | Applied pressure：50kPA Duration：12h | No leakage and no Damage | Pass
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| 9 | Insulation Resistance Measurement | GΩ | HV-LV to Ground | 2.32 | / |
| LV-HV to Ground | 2.83 | ||||
| HV&LV to Ground | 2.10 | ||||
| 10 | Oil Test | / | Dielectric Strength; | 56.1 kV | Pass |
| Moisture Content | 9.7 mg/kg | ||||
| Dissipation Factor | 0.00204% | ||||
| Furan Analysis | 0.03 | ||||
| Gas Chromatography Analysis | / |
04 Site And Summary
At SCOTECH, we deliver millions of kVA of transformers every year, worldwide. From CSA to IEEE standards, small 100 kVA units to massive 5000 kVA systems, every transformer carries our commitment to design, testing, and reliability. These two 2500 kVA units? They’re a perfect example of that expertise-engineered to perform, built to last, and ready to keep Canadian grids powered without compromise.
