Trusted transformer utility pole solutions-powering Guyana's growing grid with proven performance and engineering excellence
01 General
1.1 Project Description
In 2025, we delivered 36 units of 50 kVA single-phase pole-mounted transformers to a long-term customer in Guyana, following a successful initial order of the same model in 2024. Built to IEEE and ANSI C57.12.00 standards, each transformer features a primary voltage of 13,800 V, secondary voltage of 120/240 V, subtractive polarity, and vector group Ii0. Designed with copper windings, the units offer a 2% impedance, and include a no-load tap changer (NLTC) with a ±2×2.5% adjustment range (10% total). The no-load loss is rated at 160 W, and the load loss at 512 W, ensuring reliable performance for utility distribution applications.
This order not only reaffirms our customer’s confidence in our technical expertise and product stability but also strengthens our presence in the Guyanese utility sector. The successful delivery of these units supports local infrastructure development and enhances rural and urban power distribution networks through the deployment of reliable transformer utility pole solutions.
1.2 Technical Specification
50kVA single phase utility pole mounted transformer specification and data sheet
| Delivered to | Guyana |
| Year | 2025 |
| Type | Single phase pole mounted transformer |
| Standard | IEEE & ANSI C57.12.00 |
| Rated Power | 50KVA |
| Frequency | 60HZ |
| Polarity | Subtractive |
| Vector group | Ii0 |
| Primary Voltage | 13800V |
| Secondary Voltage | 120/240V |
| Winding Material | COPPER |
| Impedance | 2% |
| Cooling Method | ONAN |
| Tap Changer | NLTC |
| Tapping Range | ±2X2.5%(Total range=10%) |
| No Load Loss | 160W |
| On Load Loss | 512W |
| Accessories | Standard Configuration |
1.3 Drawings
50kVA single phase utility pole mounted transformer dimensions and weight details
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
 | Each transformer coil is precisely designed by our engineers in accordance with IEEE & ANSI standards. The high-voltage winding uses copper foil for better electric field distribution, while the low-voltage coil is layered with copper wire for enhanced short-circuit strength. Fully automated winding ensures consistency and quality. |
2.3 Tank
| The tank is made of mild steel with a sealed design that has passed leak testing. It offers sufficient mechanical strength to withstand shocks and vibrations during transportation, installation, and operation. Corrugated radiator groups are installed on both sides to enhance the tank’s cooling capacity, ensuring efficient heat dissipation and reliable transformer performance. |  |
2.4 Final Assembly
 | After the core and windings are inserted into the tank, transformer oil is filled for insulation and cooling. HV and LV bushings, pressure relief valve, tap changer, grounding terminal, and radiators are then installed. Finally, the exterior is cleaned, the coating quality is checked, and all labels, nameplate data, and wiring diagrams are verified for accuracy. |
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
- Oil Dielectric Test
- Leak Testing with Pressure for Liquid-Immersed Transformers
Testing Standard
- IEEE C57.12.20-2017
IEEE Standard for Overhead-Type Distribution Transformers 500 kVA and Smaller; High Voltage, 34500 V and Below; Low Voltage, 7970/13 800Y V and Below - IEEE C57.12.90-2021
IEEE Standard Test Code for Liquid-Immersed Distribution, Power, and Regulating Transformers - CSA C802.1-13 (R2022)
Minimum Efficiency Values for Liquid-Filled Distribution Transformers
Test results of single pole-mounted transformer from the 36-unit batch
| 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: Ii0 | -0.01 | Pass |
| 3 | Polarity tests | / | Subtractive | Subtractive | Pass |
| 4 | No-load losses and excitation current | % kW | I0 :: provide measured value P0: provide measured value the tolerance for no load loss is +10% | 1.08 0.086 | Pass |
| 5 | Load losses , impedance voltage,total losses 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% | 2.39 0.293 0.379 98.80 | Pass |
| 6 | Applied Voltage Test | / | HV：34KV 60s LV: 10kV 60s | No collapse of the test voltage occurs | Pass |
| 7 | Induced Voltage Withstand Test | / | Applied voltage (KV): 2 Ur Duration(s): 48 Frequency (HZ): 150 | No collapse of the test voltage occurs | Pass |
| 8 | Insulation Resistance Measurement | GΩ | HV-LV to Ground LV-HV to Ground HV&LV to Ground | 76.9 70.3 68.4 | Pass |
| 9 | Leakage Test | / | Applied pressure：20kPA Duration：12h | No leakage and No Damage | Pass |
| 10 | Oil Dielectric Test | kV | ≥45 | 58.05 | Pass |
04 Packing and Shipping
05 Site And Summary
This 50 kVA single-phase transformer utility pole is designed for the expansion of power distribution in rural and semi-urban areas of Guyana. It is particularly suitable for rural electrification, residential upgrades, and light commercial loads. The customer’s 2025 repeat order of 36 units continues the success of the initial 2024 delivery, reflecting strong confidence in the quality and reliability of our products.
Built in strict accordance with IEEE and ANSI North American standards, the transformer features a compact structure ideal for pole-top installation. It is well adapted to humid and hot environments, offering excellent heat dissipation and sealing performance to ensure reliable long-term outdoor operation. The wound core design improves energy efficiency and mechanical strength, while copper windings are arranged for enhanced short-circuit resistance. The sealed tank with corrugated radiators supports all-weather performance.
This transformer is tailored for distributed power supply and is an ideal choice for grid extension and infrastructure upgrades in remote areas, demonstrating our growing presence in the South American market.
