25kva 37.5kva 137v to 13800v Dyn11 Single Phase Oil Filled Pole Mount Transformer
1. Product Overview
The 25KVA / 37.5KVA 137V to 13800V Dyn11 Single Phase Oil Filled Pole Mount Transformer is a high-performance medium-voltage distribution transformer engineered for outdoor overhead power grid systems, fully compliant with IEC 60076 and ANSI/IEEE C57.12 international industry standards. This professional single phase pole mount transformer features a precise voltage conversion ratio of 13800V high voltage to 137V low voltage, adopting the classic Dyn11 vector group connection to deliver accurate phase shift, stable voltage output and superior current balance performance. Designed with oil-filled cooling and insulation structure, it is a core terminal power distribution device customized for low-voltage single-phase load scenarios in 13.8kV medium-voltage power grids.
Available in two mainstream rated capacities of 25KVA and 37.5KVA, this 137V to 13800V single phase oil filled transformer adopts ONAN (Oil Natural Air Natural) passive cooling technology and fully sealed oil tank design. It supports 50Hz and 60Hz dual-frequency operation, adapting to global power grid standards. Different from conventional three-phase transformers, this pole-mounted oil immersed transformer is highly targeted for scattered single-phase electrical loads, with lower no-load loss, higher operational efficiency and simpler installation. It effectively solves the voltage conversion demand from 13.8kV medium-voltage trunk lines to 137V low-voltage terminal equipment, widely applicable for residential, agricultural, commercial and outdoor engineering power distribution systems.
2. Core Product Features
2.1 Accurate Dyn11 Vector Group Performance & Stable Voltage Conversion
Equipped with standard Dyn11 connection configuration, this 25KVA/37.5KVA pole mount oil filled transformer provides precise phase angle compensation and excellent unbalanced load adaptability. The Dyn11 vector group design effectively suppresses voltage distortion and harmonic interference, ensures stable 137V low-voltage output under fluctuating grid conditions, and greatly improves the power supply quality of terminal single-phase loads. Compared with traditional Yyn0 connection transformers, it features stronger short-circuit resistance, lower zero-sequence impedance and more reliable voltage regulation performance, perfectly matching the 13800V to 137V step-down working requirements of medium-voltage single-phase distribution networks.
2.2 High-Efficiency Oil-Filled Cooling & Insulation System
As a professional single phase oil filled pole mount transformer, the product adopts high-purity mineral insulating oil as heat dissipation and insulating medium, with a fully sealed anti-leakage oil tank structure. The natural oil circulation heat dissipation system realizes uniform heat dissipation of silicon steel core and copper windings, avoiding local overheating during long-term full-load and overload operation. The oil-filled structure isolates internal electrical components from external air, preventing moisture oxidation, dust erosion and insulation aging. This mature oil immersed technology ensures continuous stable operation of the transformer in high-temperature, humid and dusty outdoor environments, with excellent insulation strength and heat dissipation efficiency.
2.3 Pole-Mounted Integrated Design & Easy Field Installation
Optimized for overhead utility pole installation, this 13800V to 137V pole mount transformer features a compact, lightweight and integrated structure. It is compatible with concrete, steel and wooden utility poles, requiring no ground foundation construction or occupied land resources. The standardized hanging fixing structure enables fast hoisting and installation, greatly shortening project construction cycles and reducing civil engineering and installation costs. Meanwhile, the open overhead installation mode facilitates natural air convection heat dissipation and daily inspection, maintenance and fault troubleshooting for power grid operators, which is far more flexible than pad-mounted and indoor transformers for scattered outdoor power distribution scenarios.
2.4 Low Loss & Energy Saving Operation
Both 25KVA single phase oil filled transformer and 37.5KVA single phase oil filled transformer adopt high-grade low-loss grain-oriented silicon steel sheets and high-density insulated copper windings. Through optimized electromagnetic circuit design, the equipment effectively reduces no-load current, iron loss and copper loss, achieving ultra-low energy consumption during long-term grid operation. Its energy efficiency indicators meet international energy-saving standards, maintaining high power conversion efficiency under light load, full load and intermittent load conditions. Long-term operation can effectively reduce power grid line loss and operational energy costs, bringing significant economic benefits for power supply enterprises and end users.
2.5 Superior Weather Resistance & Long Service Life
This outdoor pole-mounted distribution transformer is professionally designed for harsh outdoor working conditions, with rainproof, dustproof, anti-corrosion, UV-resistant and lightning protection properties. The sprayed anti-rust shell and fully sealed structure can resist extreme weather such as strong wind, heavy rain, snowstorm and high temperature, stably operating in the temperature range of -40℃ to +50℃. All internal components undergo anti-aging and anti-corrosion treatment, with a design service life of up to 30 years. The equipment features ultra-low failure rate and minimal daily maintenance, ensuring long-term reliable operation of outdoor power distribution systems.
2.6 Complete Safety Protection & High Operational Reliability
The Dyn11 single phase pole mount transformer is equipped with multiple built-in safety protection mechanisms, matching external surge arresters and fuse cutouts to form a comprehensive protection system against overvoltage, overcurrent, short circuit and lightning surge. The pressure relief and explosion-proof oil tank structure can safely release internal pressure in case of abnormal faults, preventing oil leakage, explosion and other safety accidents. All products pass strict factory aging tests, partial discharge tests and insulation tests, with stable electrical performance and high safety factor, meeting the safety operation specifications of public power grids and industrial and civilian power supply systems.
3. Core Usage
The core function of the 25KVA/37.5KVA 137V-13800V oil filled pole mount transformer is precise medium-to-low voltage step-down conversion and terminal power distribution in single-phase 13.8kV overhead power grids. It mainly converts 13800V medium-voltage high-power electric energy transmitted by overhead trunk lines into standard 137V low-voltage electric energy, providing compliant and stable power supply for various single-phase low-voltage electrical equipment.
In actual power grid operation, this Dyn11 vector group transformer also undertakes key functions such as grid voltage stabilization, unbalanced load adjustment and electrical isolation. It can effectively suppress voltage fluctuation and harmonic interference caused by scattered terminal loads, improve the stability and quality of terminal power supply, and isolate local line faults to prevent fault diffusion and avoid large-area power outages. In addition, it realizes reasonable shunting and distribution of medium-voltage grid power, improves the utilization rate of power grid resources, and solves the power supply pain points of decentralized single-phase loads that cannot be covered by conventional three-phase power distribution equipment.
4. Application Scenarios
4.1 Rural Power Grid Renovation & Rural Power Distribution
This 13800V to 137V single phase pole mount transformer is the preferred core equipment for rural medium-voltage power grid renovation and rural electrification projects. It is perfectly adapted to the characteristics of scattered rural households, long power supply lines and decentralized single-phase loads. The 25KVA model is suitable for single household power supply, rural street lighting, small agricultural irrigation pumps and rural household electrical equipment; the upgraded 37.5KVA model can meet the centralized power demand of rural small processing workshops, breeding bases and village public service facilities, effectively solving the problem of unstable voltage and difficult power supply in remote mountainous and pastoral areas.
4.2 Low-Voltage Industrial Equipment Power Supply
Widely used for power supply of low-voltage single-phase industrial equipment that requires 137V working voltage, including small mechanical processing equipment, precision testing instruments, light industrial production lines and field engineering electrical equipment. The precise 13800V to 137V voltage conversion and Dyn11 harmonic suppression performance can effectively protect precision electrical equipment from voltage impact and power quality interference, ensuring the stable operation of industrial production and testing equipment.
4.3 Outdoor Public Facilities & Monitoring System Power Supply
The weather-resistant oil filled single phase pole mount transformer is widely applied in outdoor unattended scenarios, including urban and rural road monitoring systems, highway traffic facilities, scenic area service equipment, communication base station auxiliary power supply and remote meteorological monitoring equipment. Its pole-mounted installation does not occupy ground space, and long-term stable outdoor operation performance fully meets the power supply demand of decentralized outdoor public facilities.
4.4 Suburban & Light Commercial Power Distribution
Suitable for power supply of suburban scattered residential areas, single-family villas, roadside convenience stores and small commercial studios. The single-phase power supply mode avoids idle energy loss of large three-phase transformers, and the low-noise, pollution-free oil-filled operation design will not interfere with living and business environments, achieving energy-saving and economical terminal power distribution for light commercial and civilian scenarios.
5. FAQ (Frequently Asked Questions)
5.1 What is the advantage of Dyn11 vector group for this 13800V/137V single phase transformer?
The Dyn11 vector group configuration is the core advantage of this pole mount oil filled transformer compared with ordinary transformers. Firstly, it provides accurate phase angle compensation, effectively suppressing voltage harmonics and waveform distortion to improve terminal power supply quality. Secondly, Dyn11 connection features lower zero-sequence impedance and stronger unbalanced load adaptability, which can stably cope with uneven single-phase load operation. In addition, it has better short-circuit resistance and fault tolerance, reducing equipment damage risks caused by grid short-circuit faults, making it more suitable for complex outdoor medium-voltage single-phase power grid operation environments.
5.2 How to choose between 25KVA and 37.5KVA models for practical use?
The selection of 25KVA and 37.5KVA single phase oil filled pole mount transformers depends on actual load power and future expansion demand. The 25KVA model is suitable for small-scale scattered loads such as single household power supply, single monitoring equipment and small agricultural machinery, with lower no-load loss and more energy-saving daily operation. The 37.5KVA model has higher load bearing capacity, suitable for multi-household centralized power supply, small industrial equipment and multi-channel electrical equipment simultaneous operation. It reserves sufficient load margin for future electrical equipment upgrading, avoiding equipment replacement caused by load increase.
5.3 What are the maintenance requirements for outdoor oil-filled pole-mounted transformers?
This 137V to 13800V Dyn11 pole mount transformer features low daily maintenance cost and simple operation. It is only necessary to regularly check the firmness of pole fixing parts, whether the shell is corroded or oil-leaking, and whether the wiring terminals are loose and oxidized. Inspect the insulating oil level and oil quality every 1-2 years to ensure normal heat dissipation and insulation performance. In thunderstorm and rainy seasons, check the working state of matching lightning protection and fuse protection devices. With standard regular inspection, the equipment can maintain stable operation for decades without frequent component replacement or oil replacement.
