Minimal Footprint, Maximum Reliability – Pole Mounted Transformers for Efficient Power Delivery.
01 General
1.1 Project Description
100 kVA single phase pole mounted transformer was delivered to Canada in 2025. The rated power of the transformer is 100 kVA with ONAN cooling. The primary voltage is 24.94GrdY/14.4 kV with ±2*2.5% tapping range (NLTC), the secondary voltage is 0.347 kV, they formed a vector group of Ii6.
This 100 kVA pole-mounted transformer is engineered for high-performance power distribution in overhead electrical networks, combining reliability, safety, and adaptability for both rural and urban applications. Designed to withstand demanding environmental and operational conditions, it incorporates critical protective and functional components to ensure uninterrupted service and extended operational life.
Key features include a pressure relief device to safely vent excess pressure in case of internal faults, minimizing the risk of tank rupture. The integrated arrester support provides secure mounting for surge arresters, enhancing protection against lightning strikes and voltage transients. For advanced fault detection, the transformer is equipped with an Internal Fault Detector (IFD), enabling early identification of abnormalities to prevent catastrophic failures. Additionally, the off-circuit tap changer allows for flexible voltage adjustment (when de-energized), ensuring optimal performance under varying load conditions.
Built for durability and ease of maintenance, this transformer delivers efficient energy distribution while prioritizing safety and operational resilience, making it an ideal solution for modern power infrastructure.
1.2 Technical Specification
100 kVA pole mounted transformer specifications type and data sheet
| Delivered to | Canada |
| Year | 2025 |
| Type | Pole mounted transformer |
| Standard | CSA C2.2-06 |
| Rated Power | 100 kVA |
| Frequency | 60HZ |
| Phase | 1 |
| Polarity | Additive |
| Cooling Type | ONAN |
| Primary Voltage | 24.94GrdY/14.4 kV |
| Secondary Voltage | 0.347 kV |
| Winding Material | Aluminum |
| Angular displacement | Ii6 |
| Impedance | 3% |
| Tap Changer | NLTC |
| Tapping Range | ±2*2.5% |
| No Load Loss | 0.195 kW |
| On Load Loss | 1.52 kW |
| Accessories | Standard Configuration |
1.3 Drawings
100 kVA pole mounted transformer diagram drawing and size.
02 Manufacturing
2.1 Core
| The silicon steel strip is wound continuously using precision machinery, resulting in a joint-free core with a uniform magnetic path, reducing hysteresis loss and noise. The seamless design minimizes magnetostriction-induced vibrations, resulting in 5-10 dB lower noise levels than laminated cores. The symmetrical magnetic path enhances resistance to DC bias, making it suitable for distribution networks with significant voltage fluctuations. The high space efficiency of wound cores suits the compact size requirements of pole-mounted transformers, compatible with both shell-type and core-type winding arrangements. |  |
2.2 Winding
 | Pole-mounted transformers adopt an optimized aluminum foil LV + copper wire HV winding design: The LV side uses helically wound aluminum foil (0.2–1.0mm) for better cooling, cost efficiency, and short-circuit resistance, while the HV side employs layer wound copper windings for higher conductivity and voltage ratings (up to 72.5kV). An insulating pressboard barrier and vacuum impregnation enhance dielectric strength. The foil’s large surface area improves heat dissipation, and copper’s high current density ensures compactness. This hybrid solution balances economy (Al) and reliability (Cu), reducing no-load losses by 15-25%, making it ideal for distribution networks. |
2.3 Tank
| Our products comply with C4 corrosion resistance classification. The following technical enhancements ensure superior performance: 1- Process Control Reinforcement Optimized surface pretreatment processes are adopted, with strict cleaning and chemical treatment procedures to completely eliminate substrate contamination while guaranteeing full compliance with coating thickness specifications. 2- Structural Optimization Full-seam sealing technology is applied to critical welds, effectively blocking moisture penetration into internal transformer components and significantly improving long-term operational reliability. |  |
2.4 Final Assembly
 | 1. Winding Installation: Slide the high-voltage and low-voltage windings onto the laminated core, ensuring proper insulation alignment and secure mechanical fixation. 2. Electrical Connections: Connect winding leads to the tap changer, bushings, and other components, then verify contact resistance. 3. Core-Coil Drying: Place the assembled active part (core + windings) into a drying oven for vacuum heating to remove moisture and ensure insulation integrity. 4. Tank Placement: Hoist the dried active part into the tank and secure it with base bolts. 5. Accessory Installation: Mount bushings, IFD, pressure relief valve, and other accessories, sealing all joints. 6. Oil Filling & Sealing: Vacuum-fill insulating oil to the specified level, then test oil quality and tank tightness after settling. |
03 Testing
| No. | Test Item | Unit | Acceptance Values | Measured Values | Conclusion |
| 1 | Resistance Measurements | / | / | / | Pass |
| 2 | Ratio Tests | / | The deviation of voltage ratio on the principal tapping: ≤0.5% Connection symbol: Ii6 | -0.04 | Pass |
| 3 | Polarity tests | / | Additive | Additive | Pass |
| 4 | No-load losses and excitation current | % | I0 :: provide measured value（100%） | 0.17 | Pass |
| kW | P0: provide measured value（100%） | 0.161 | |||
| % | I0 :: provide measured value（105%） | 0.33 | |||
| kW | P0: provide measured value（105%） | 0.204 | |||
| / | the tolerance for no load loss is +15% | / | |||
| 5 | Load losses , impedance voltage,total losses and efficiency | / | t:85℃ the tolerance for impedance is ±7.5% the tolerance for total load loss is +8% | / | Pass |
| % | Z%: measured value | 3.16 | |||
| kW | Pk: measured value | 1.377 | |||
| kW | Pt: measured value | 1.538 | |||
| % | Efficiency not less than 98.94% | 99.07 | |||
| 6 | Applied Voltage Test | / | LV: 10kV 60s | No collapse of the test voltage occurs | Pass |
| 7 | Induced Voltage Withstand Test | / | Applied voltage (KV):2Ur | No collapse of the test voltage occurs | Pass |
| Duration(s):48 | |||||
| Frequency (HZ): 150 | |||||
| 8 | Insulation Resistance Measurement | GΩ | LV-HV to Ground | 43.3 | Pass |
| 9 | Leakage Test | / | Applied pressure：20kPA | No leakage and no Damage | Pass |
| Duration：12h | |||||
| 10 | Oil Test | kV | Dielectric Strength | 57.4 | Pass |
| mg/kg | Moisture Content | 9.3 | |||
| % | Dissipation Factor | 0.00254 | |||
| mg/kg | Furan Analysis | 0.03 | |||
| / | Gas Chromatography Analysis | / |
04 Packing and Shipping
4.1 Packing
| The single-phase pole-mounted transformer is packed in an anti-corrosion wooden crate, internally secured with bolts and shock-absorbing rubber pads, and fragile parts are protected with foam. The crate is wrapped in UV-resistant rainproof fabric, fastened with nylon straps, and the seams are sealed. Ventilation holes are included on top. The packaging features lifting marks, desiccants, and a waterproof document pouch, ensuring suitability for sea and outdoor transport. |  |
4.2 Shipping
 | Under CIF terms, the seller ships pole-mounted transformers to Montreal Port, Canada, covering cost, marine insurance, and freight. Transformers are securely crated (wooden/steel frames) and shipped via ocean freight (container or breakbulk), with All Risks insurance. Upon arrival, the buyer handles customs clearance and final truck delivery. Key documents include B/L, commercial invoice, packing list, and insurance certificate. Challenges include winter weather protection and customs delays. |
05 Site And Summary
Pole-mounted transformers offer a compact, cost-effective, and reliable solution for overhead power distribution in urban and rural networks. Designed for durability and easy installation, they ensure efficient voltage transformation with minimal maintenance. Whether for utilities, industrial applications, or renewable energy integration, our transformers meet international standards (IEEE, IEC, CSA) and are built for harsh environments. Contact us today for customized solutions tailored to your grid requirements.
