Efficient, reliable, and eco-friendly—powering your distribution network with Scotech’s 50 kVA pole-mounted transformer
01 General
1.1 Project Description
This 50 kVA single-phase transformer on power line is manufactured by Scotech and exported to Canada. The transformer fully complies with IEEE C57.12.20 standards, ensuring reliable performance for residential and light commercial distribution networks.
This order includes 20 units of single-phase pole-mounted transformers, among which 5 units are of this 50 kVA model. Each transformer is designed for a primary voltage of 7.97/13.8Y kV and a secondary voltage of 277 V, featuring two high-voltage bushings and two low-voltage bushings. The transformer is equipped with a no-load tap changer (NLTC) with a ±2×2.5% range.
The 50 kVA transformer on power line uses an amorphous alloy core, reducing no-load loss to 0.043 kW and load loss to 0.5 kW. It is energy-saving and environmentally friendly, reducing electricity costs.
The transformer weighs 327 kg, including 81 kg of insulating oil. The oil helps with cooling and insulation. Its size is 645 × 715 × 1115 mm. The small and balanced design fits well on a pole-mounted power line. A surge arrester boss allows easy integration of protective devices, enhancing reliability and safety.
Designed with aluminum windings, additive polarity, and ONAN natural cooling, this transformer on power line is compact, efficient, and highly reliable. Aluminum construction and smart design provide a flexible solution for modern power distribution systems, ensuring energy efficiency and dependable performance.
1.2 Technical Specification
50kVA Single phase pole mounted transformer specification and data sheet
| Delivered to | Canada |
| Year | 2024 |
| Type | Single phase pole mounted transformer |
| Standard | IEEE C57.12.20 |
| Rated Power | 50KVA |
| Frequency | 60HZ |
| Polarity | Additive |
| Vector group | Ii6 |
| Primary Voltage | 7.97/13.8Y kV |
| Secondary Voltage | 277 V |
| Winding Material | Aluminum |
| Impedance | 2.1% |
| Cooling Method | ONAN |
| Tap Changer | NLTC |
| Tapping Range | ±2X2.5% |
| No Load Loss | 0.043 KW |
| On Load Loss | 0.5 KW |
| Accessories | Surge arrester boss |
1.3 Drawings
50kVA transformer on power line dimensions and weight details
02 Manufacturing
2.1 Core
| The transformer uses an amorphous metal core, an isotropic soft magnetic material with high resistivity, greatly reducing eddy current losses. Compared to cold-rolled silicon steel, it lowers core loss by 70–80%, achieving a no-load loss of 0.043 kW and load loss of 0.5 kW. Its thin 0.03 mm ribbons simplify manufacturing, improve efficiency, and offer an energy-saving, eco-friendly solution. |  |
2.2 Winding
 | Optimized coil design features foil-wound low-voltage coils and wire-wound high-voltage coils. Customers may choose aluminum for the LV coil, reducing cost and weight while maintaining reliability and lifespan similar to copper. Polarity is additive and the transformer follows vector group Ii6, providing correct phase relationships and reliable operation. |
2.3 Tank
| Designed for pole mounting, this transformer tank is finished in light grey and constructed from high-quality low-carbon steel using a drawing process to create a cylindrical structure. The tank body utilizes integral sealing technology, with the cover and bottom formed from sheet metal stamping, reducing weight while ensuring structural strength. |  |
2.4 Final Assembly
 | Active Part Cleaning & Fastening
Remove all metal and visible non-metal debris.
Tighten yoke and base bolts. Secure tie-band, lock nuts, wire clamps, supports, brackets, and outer screen bolts; ensure insulation parts align. Apply axial pressure symmetrically on HV/LV sides, at least 2 cycles. Tighten wires and potential connection bolts with torque wrench.
Check insulation and leads for damage or dirt. Ensure no missing parts. Count all tools used. |
03 Testing
Routine Test
- Resistance Measurements
- Ratio Tests
- Polarity Test
- No Load Losses and No Load Current
- Load Losses and Impedance Voltage
- Applied Voltage Test
- Induced Voltage Withstand Test
- Insulation Resistance Measurement
- Leak Testing with Pressure for Liquid Immersed Transformers
- Oil Dielectric Test
Test Results
| 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 | -0.17 | Pass
|
| 3 | phase-relation tests | / | Additive | Additive |
Pass
|
| 4 | No-load losses and excitation current | % kW | t:85℃ I0 :: provide measured value P0: provide measured value the tolerance for no load loss is +10% | 1.20(100%) 2.35(105%) 0.043(100%) 0.056(105%) | 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 ±10% the tolerance for total load loss is +6% | 2.28 0.481 0.526 99.39 | Pass
|
| 6 | Applied Voltage Test | kV | HV: 34kV 60s LV：10kV 60s | No collapse of the test voltage occurs | Pass
|
| 7 | Induced Voltage Withstand Test | kV | Applied voltage (KV): 15.94 Duration(s):40 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: | 51.7 | / |
| HV-LV to Ground | 24.5 | ||||
| LV-HV to Ground | 31.5 | ||||
| 10 | Oil Dielectric Test | kV | ≥45 | 52.05 | Pass
|
| 11 | Lightning impulse test | kV | full wave, Half wave | No collapse of the test voltage occurs | Pass
|
04 Packing and Shipping
05 Site and Summary
The 50 kVA single-phase pole-mounted transformerdelivered to Canada in 2024 shows Scotech’s focus on quality, efficiency, and innovation. It has an amorphous metal core, aluminum windings, and ONAN natural cooling. This design lowers losses, works reliably, and saves energy for residential and light commercial networks. Its compact, pole-mounted design, robust tank, and integrated surge arrester boss ensure safety, durability, and ease of installation.
Scotech makes high-performance, eco-friendly transformers for modern power systems. This project shows our skill in engineering, manufacturing, and quality control. We provide reliable products that save energy and improve grid performance.
