100 kVA single-phase pole mounted transformer-built for stable power in low-density, long-distance distribution areas
01 General
1.1 Project Description
This 100 kVA single-phase pole mounted transformer, delivered to Guyana in 2025, is designed in compliance with IEEE and ANSI C57.12.00 standards. With a primary voltage of 13,800 V and a secondary voltage of 120/240 V, it is ideal for residential or light commercial distribution in rural or suburban areas where single-phase service is required. The ONAN cooling, copper windings, and subtractive polarity ensure high reliability and durability in outdoor environments. Its ±2×2.5% NLTC tap changer allows for minor voltage regulation, making it suitable for areas with voltage fluctuation or long-distance transmission. The compact, 100 kVA pole mounted transformer design is especially effective for cost-efficient deployment in regions with low population density.
1.2 Technical Specification
100kVA single phase 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 | 100KVA |
| 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 | 263W |
| On Load Loss | 1160W |
| Accessories | Standard Configuration |
1.3 Drawings
100kVA single phase pole mounted transformer dimensions and weight details
02 Manufacturing
2.1 Core
| In transformer manufacturing, the core plays a vital role as the main path for magnetic flux, directly affecting performance and efficiency. In the image, multiple rolled cores are neatly arranged after passing dimensional checks and positioning. Workers follow standardized procedures to ensure tight, aligned lamination, preparing the cores for precise coil assembly and the next stage of active part construction. |  |
2.2 Winding
 | The 100kVA single phase pole mounted transformer uses copper windings. The low voltage coil adopts foil winding with high-conductivity copper foil, wound tightly with layered insulation. The high voltage coil uses enamelled copper wire, precisely wound with insulation between layers. After winding, coils are vacuum dried and cured to enhance insulation strength and long-term reliability. |
2.3 Tank
| The mild steel oil tank, with corrugated radiators on both sides, undergoes careful quality checks before assembly. In the image, workers are performing dimensional checks by measuring key parts, conducting visual inspections to spot surface defects or weld issues, and verifying the surface treatment condition. These thorough checks ensure the oil tank meets the required standards for reliable transformer performance. |  |
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
| No. | Test Item | Unit | Acceptance Values | Measured Values | Conclusion |
| 1 | Resistance Measurements | / | / | / | Pass |
| 2 | Ratio Tests | / | The deviation of the voltage ratio on the principal tapping: ≤0.5% Connection symbol: Ii0 | -0.03 | 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% | 0.49 0.225 | 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% | 2.33 0.857 1.082 99.17 | 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 | 35.9 17.4 16.2 | Pass |
| 9 | Leakage Test | / | Applied pressure：20kPA Duration：12h | No leakage and no Damage | Pass |
| 10 | Oil Dielectric Test | kV | ≥45 | 56.41 | Pass |
04 Packing and Shipping
05 Site And Summary
This 100kVA single-phase pole-mounted transformer is ideal for outdoor distribution in rural or suburban areas where a 13.8kV primary voltage steps down to 120/240V secondary voltage. Featuring copper windings, ONAN natural cooling, and a ±2×2.5% no-load tap changer, it offers high reliability and flexible voltage regulation-perfect for regions with voltage fluctuations or long-distance power delivery. Its compact design and easy pole mounting make it cost-effective for low-density population areas.
If your project requires:
• Low to medium capacity single-phase power
• Outdoor pole-mounted installation
• Stable voltage under fluctuating or extended distribution lines
• Efficient copper windings and natural cooling to reduce maintenance costs
This pole mounted transformer is an excellent fit. Contact us for more details and customization options.
