25 kVA Pole Mounted Transformer | Ultra-Low Loss Single Phase
OMEK 25 kVA Pole Mounted Transformer powers a variety of light commercial, residential distribution (2-4 homes), utilities, and rural electrification. Low noise, excellent heat dissipation and a 30-year life in extreme environment from CRGO steel cores and high purity copper/aluminium windings.
Rated Capacity: 25 kVA
Primary Voltage: Up to 34.5 kV
Secondary Voltage: 120/240V, 220/230V
Efficiency Standard: DOE 2016 / IEEE C57.12.20
Weight & Dimensions: Weight: ~250-360 kg (550-790 lbs); Height: ~33-40 inches
Core Components
OMEK 25 kVA aerial transformers have high permeability CRGO silicon steel cores with pure copper or aluminum low/high-voltage windings.
The transformers are designed with porcelain high-voltage bushings on top with BIL ratings from 95 kV to 150 kV, and low-voltage stud bushings with BIL ratings of 30 kV.
A 25 kVA pole type transformer has an automatic pressure relief valve, lifting lugs and an external tap changer (typically 5 position, ± 2× 2.5%).
OMEK offers you two options: conventional type with external drop-out fuses and lightning arresters installed yourself or CSP type with internal primary fuses, secondary breakers and surge arresters directly on the tank.
What Makes OMEK 25 kVA Overhead Transformer Different?
With precision-laminated cold-rolled grain-oriented (CRGO) silicon steel core, OMEK 25 kVA overhead transformer offers no-load losses as low as 65 W – 104 W, surpassing the 2016 DOE efficiency standards.
Pressure relief valves, tap changers, and oil sampling ports allow for on-pole inspection and maintenance. Critical parts are stored for rapid delivery within 24 – 48 hours to reduce downtime in the grid.
After 1000+ hours of salt spray testing, the corrosion resistance will not diminish in sealed steel tank with special multi-layer coating, offering long-lasting structural integrity in salty, tropical or humid areas.
100% high-purity copper windings minimize internal electrical resistance and maximize thermal dissipation. They can safely run up to 110% continuous overload within the 65 ℃ winding limit.
Technical Specs: OMEK 25 kVA Single Phase Overhead Transformer
D13‑M vs. D11‑M Performance Comparison
| Technical Specs | D13‑M Series (Ultra‑Low Loss Core) | D11‑M Series (Standard Efficiency) |
|---|---|---|
| Phase | Single phase | Single phase |
| High Voltage (kV) | 6 / 6.3 / 10 / 10.5 / 11 | 6 / 6.3 / 10 / 10.5 / 11 |
| Low Voltage (kV) | 2 × (0.22~0.24) or 0.22~0.24 | 2 × (0.22~0.24) or 0.22~0.24 |
| Frequency (Hz) | 50, 60 | 50, 60 |
| Tapping Range | ± 2×2.5% | ± 2×2.5% |
| Total Weight (kg) | 250‑360 | 250‑360 |
| Connected Group Label | Ii0, Ii6 | Ii0, Ii6 |
| No‑Load Loss (W) | 64 | 80 |
| Load Loss (W) | 560 | 560 |
| No‑Load Current (%) | 0.8 | 0.8 |
| Short Circuit Impedance (%) | 3.0 | 3.0 |
| Cooling Type | ONAN | ONAN |
| Temperature Rise | 65 ℃ | 65 ℃ |
| Enclosure Protection Rating | IP54, IP65 | IP54, IP65 |
| Overall Dimension (L×W×H, inches) | 22.2 × 19.7 × 40.8 | 22.2 × 19.7 × 40.8 |
| Mounting Dimension (L×W, inches) | 9.8 × 17.7 | 9.8 × 17.7 |
OMEK Takeaway: OMEK D13‑M series provides a 20% reduction in core loss, saving approximately 140 kWh per year per transformer in continuous grid standby mode.
Application & Field Performance
Rural Residential Distribution
Application Scene: Multi-drop secondary power for scattered homes and remote farming communities.
OMEK Solution: OMEK supplied 120 units of 25 kVA pole mounted transformers for a rural electrification upgrade in South America in 2024. The units ran on a 12.47 kV primary circuit and provided 240V split-phase service to 2-3 homes per pole. The local electric cooperative saved 18% off-peak line losses with the ultra-low 64W core loss (D13-M series).
Agricultural Power Distribution
Application Scene: Irrigation pumping, cold storage, and livestock barn equipment.
OMEK Solution: A commercial dairy farm in Southeast Asia needed localized voltage isolation for 15 HP deep-well water pumps and milk cooling tanks. OMEK provided 25 kVA transformers with 110% continuous overload capability. The 1,000-hour salt-spray resistant tanks effectively prevented corrosion in high-ammonia environment, maintaining stable 230V single-phase power without single-phase tripping.
Commercial & Light Industrial Step-Down Loads
Application Scene: Auxiliary power for cell towers (telecom), roadside service stations, and small workshops.
OMEK Solution: A large telecom tower company installed OMEK 25 kVA transformers to reduce 11 kV line power for remote 5G base stations. The compact 22.2″ × 19.7″ footprint allowed direct single-pole mounting without reinforced crossarms, reducing installation costs by 25% and ensuring stable, low-noise for sensitive equipment.
Renewable Energy & Distributed Solar Backfeed
Application Scene: Step-up / grid-tied isolation for rooftop PV arrays and distributed solar systems.
OMEK Solution: In a distributed 20 kW residential solar project, OMEK 25 kVA transformers were selected as the grid-interconnection interface. Designed with custom two-way voltage regulators and high heat-resistant copper windings, OMEK transformers sent reliable solar power to the grid without voltage degradation or core saturation.
Get Your Customized 25 kVA Pole Mounted Transformer?
Just tell us your specs: phase number, winding material, high/low voltage, frequency, no-load Loss and load loss. Missing some numbers? No problem. Tell us your application and grid standard — our engineers will help you determine the rest. Contact OMEK now!
Why Choose OMEK – Your Trusted Partner for 25 kVA Transformers
Real Production Bases & Live Factory Audits
100% Physical Manufacturing Bases: OMEK has 2 production bases and 1 copper-based industrial park, supported by 6 automated production lines to control core quality from raw material to finished products.
Factory Audits Supported: OMEK welcomes third-party factory audits (SGS, TÜV, BV, Intertek) and offers live video inspection before shipment.
Trial Orders Supported & 24-Hour Rapid Response
Trial Orders Supported: OMEK accepts trial orders (MOQ: 1 unit), so you can test our quality before closing the deal of full container load.
Rapid Response: Get technical drawing, wiring diagram, and quotations within 24 hours.
Complete Compliance & Full Test Reports
Standards Compliance: IEC, IEEE/ANSI, RETIE, INMETRO, SONCAP, KEBS, SABS, PCCC Energy-Saving.
Certifications & Qualifications: CE, ASTA, ISO 9001/14001/45001, CCC, CQC, ILAC-MRA Test Reports, SGS/BV Inspected）.
Full Test Reports: OMEK products strictly undergo incoming material inspection, routine tests (100% full inspection), type tests (sampling inspection), and special tests as requested.
Guaranteed Lead Time & On-Time Delivery
On-Time Delivery: OMEK maintains a 99% on-time shipment record, ensuring your projects stay on schedule.
Reliable Packaging: Custom wooden boxes ensure zero damage during sea or other transport.
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FAQs
Have any questions? We’re here to help you out.
A 25 kVA pole top transformer typically weighs 250-360 kg (550 lbs to 790 lbs). It varies mainly depending on copper/alluminum windings, core efficiency class, protection types and mineral oil.
It depends on the secondary output voltage.
Take 240V for example.
According to the equation: Amps=kVA × 1000 ÷ Voltage, specifically for a 25 kVA at 240V: Amps=25 × 1000 ÷ 240=104.17 A.
Therefore, the 25 kVA overhead transformer rated current is 104.17A at 240V.
A 25 kVA pole mounted transformer can power:
2 – 4 households running air conditioners, cooking appliances and TVs simultaneously
One deep-well agricultural pump with 15-20 horsepower plus lighting in several greenhouses
One telecom base station or gas station in continuous operation
kVA≠kW! The actual power (kW) of a 25 kVA overhead transformer is not its rated capacity. It depends on the power factor of your connected equipment. kW = kVA × PF.
For example,
Heaters & lighting (PF: 1.0): 25 kW
Residential & Commercial (PF: 0.9): 22.5 kW
Motors, pumps and HVAC compressors (PF: 0.8): 20 kW
No more than 80% of their rated capacity.
A pole mounted transformer base is usually located 12 to 15 feet (3.6 to 4.5 meters) above the ground.
An upgraded system from old 10 kVA overhead transformer to 25kVA pole top transformer can safely return excess power to the grid on peak solar generation without causing voltage issues.
In many areas the local power company pays for the new transformer as part of their standard permit program for solar installations.
OMEK standard lead time is around 30 days from order confirmation.
It also depends on your order quantity.