Substation Class
69kV 33kV 10MVA 20MVA 30MVA ONAN Copper Oil Immersed Power Transformer
33kV / 69kV Class
ONAN Cooling
Copper Winding
Engineered for overhead utility networks, industrial step-down substations, commercial developments, and renewable power step-up applications across Great Britain.
The United Kingdom's electricity distribution network is undergoing its most radical architectural transition in decades. As Distribution Network Operators (DNOs)—including UK Power Networks (UKPN), National Grid Electricity Distribution (NGED), SP Energy Networks, Northern Powergrid, SSEN, and Electricity North West—accelerate network reinforcement to support Net Zero 2050 initiatives, the demand for high-reliability, low-loss pole-mounted distribution transformers has expanded exponentially.
Pole-mounted transformers (PMTs) serve as the vital linchpin between high-voltage overhead distribution lines (typically operating at 11kV or 33kV) and end-user low-voltage supplies (400V 3-phase / 230V single-phase). In rural agricultural zones across Yorkshire, Wales, the East Midlands, and the Scottish Highlands, these assets endure severe environmental stressors, ranging from coastal salt spray to extreme wind loads.
Procuring pole-mounted transformers for the UK market requires precise alignment with British Standards (BS EN 60076 series), Energy Networks Association Technical Specifications (notably ENA TS 35-1), and retained UK legislation governing maximum allowable losses (EcoDesign Regulation EU 2019/1783 Tier 2 compliance).
Primary Voltages: 11kV, 33kV (50Hz System Frequency)
Secondary Voltages: 400V 3-Phase / 230V Single-Phase (Custom 480V available)
Cooling Classifications: ONAN (Oil Natural Air Natural), KNAN (Ester Fluid)
Standard Ratings: 16kVA, 25kVA, 50kVA, 100kVA (Single Phase); 50kVA to 500kVA (3-Phase)
Corrosion Protection: Hot-Dip Galvanised Tanks to BS EN ISO 1461, C4/C5 Marine Paints
Discover how specialized pole-mounted step-down transformers solve specific geographical, load profile, and grid code challenges within the UK electrical landscape.
Supplying continuous 230V/400V power to remote farms, grain silos, and rural residential clusters across Wales, Devon, and the Scottish Borders via 11kV overhead spur lines. Built with low no-load loss profiles ($P_o$) for highly seasonal agricultural electricity usage.
Platform and pole-mounted transformers deployed alongside major transport corridors (A1(M), M1, M6) to step down 11kV primary distribution for ultra-rapid EV charging points. Designed to handle severe non-linear harmonic distortion with K-factor rating capability.
Deployments in high-salinity coastal areas such as Cornwall, East Anglia, and Aberdeenshire. Features C4/C5-M atmospheric corrosion class coating, stainless steel tank fittings, and sealed bushings designed to withstand persistent salt spray and high atmospheric moisture.
Stepping up low-voltage AC outputs from distributed solar arrays and battery energy storage systems (BESS) directly to the 11kV overhead distribution grid. Engineered with bi-directional power flow withstand and transient overvoltage protection.
1. Strict EcoDesign Tier 2 Loss Capitalization: The UK government retained the stringent EcoDesign (EU 2019/1783) Tier 2 loss mandates post-Brexit. UK procurement engineers evaluate bids using Total Cost of Ownership (TCO) formulas: $TOC = CC + A \times P_o + B \times P_k$, placing maximum value on ultra-low core loss ($P_o$) through high-grade CRGO and amorphous alloy cores.
2. Adoption of Biodegradable Synthetic & Natural Esters: To satisfy UK Environment Agency guidelines near waterways and National Parks (such as the Lake District and Peak District), utilities are shifting away from traditional mineral oil toward non-toxic, fire-safe K-class ester fluids like Midel 7131 or FR3.
3. Smart Grid Telemetry & Remote Condition Monitoring: Modern UK distribution lines require transformers equipped with digital oil temperature indicators (OTI), tank pressure sensors, and wireless DGA (Dissolved Gas Analysis) interfaces for predictive maintenance via DNO SCADA systems.
Detailed comparison of electrical, mechanical, and thermal design parameters tailored to UK electrical network specifications.
| Parameter | Single-Phase Pole Mounted | Three-Phase Pole Mounted | Cast Resin Dry-Type | Substation Power Class |
|---|---|---|---|---|
| Power Rating Envelope | 16 kVA – 100 kVA | 50 kVA – 500 kVA | 100 kVA – 4500 kVA | 1 MVA – 30 MVA |
| Primary Voltage (HV) | 11 kV / 33 kV | 11 kV / 33 kV | 11 kV / 20 kV / 33 kV | 33 kV / 69 kV / 132 kV |
| Secondary Voltage (LV) | 230V / 460V Split Phase | 400V / 230V 3-Phase 4-Wire | 400V / 415V / 433V | 11 kV / 6.6 kV / 0.4 kV |
| Cooling Designation | ONAN / KNAN | ONAN / KNAN | AN / AF (Air Natural / Forced) | ONAN / ONAF / OFWF |
| Loss Benchmark | EcoDesign Tier 2 (EN 50588-1) | EcoDesign Tier 2 (EN 50588-1) | EN 60076-11 Tier 2 | IEC 60076-1 Custom A&B |
| Vector Group | Ii0 / Single-Phase | Dyn11 / Dyn1 | Dyn11 / Yyn0 | Dyn11 / Yd11 |
| Tank / Enclosure | Hermetically Sealed / Galvanised | Hermetically Sealed Steel | IP23 / IP54 Kiosk | Conservator / Corrugated |
| Dielectric Fluid | Mineral Oil / Midel 7131 Ester | Mineral Oil / Synthetic Ester | N/A (Epoxy Cast Resin) | Mineral Oil / High-Flash Fluid |
Rooted in over two decades of precision manufacturing excellence from our state-of-the-art facility in Rajkot, Gujarat.
Our continuous copper and aluminium foil-winding machinery replaces conventional wire windings. This completely eliminates axial short-circuit forces, reduces internal hot-spot temperature rise, and guarantees superior structural integrity under heavy grid fault conditions.
Utilising prime-grade, domain-refined Cold-Rolled Grain-Oriented (CRGO) silicon steel sourced directly from world-class mills. Precision step-lap miter cutting inside our factory ensures minimal no-load losses ($P_o$), meeting UK Tier 2 efficiency curves.
Every single unit undergoes comprehensive routine testing prior to dispatch, including insulation resistance, winding resistance, voltage ratio, vector group, partial discharge, separate-source AC withstand, and full-load loss verification with official test certificates.
Addressing common engineering, compliance, and shipping queries from UK electrical contractors, utility buyers, and consultants.
Our engineering team designs core-coil assemblies using top-tier CRGO silicon steel and optimized step-lap joints. This guarantees that load losses ($P_k$) and no-load losses ($P_o$) strictly satisfy or exceed the maximum loss limits mandated by EU 2019/1783 Tier 2 (retained UK law) and BS EN 50588-1.
Yes. Our pole-mounted and ground-mounted transformers are custom-engineered to match UK DNO system parameters, including 11kV or 33kV primary distribution voltages, 50Hz frequency, specific vector groups (such as Dyn11), and standard UK bushing configurations.
We offer hot-dip galvanising to BS EN ISO 1461 as well as multi-layer epoxy C4/C5 marine-grade paint systems. Tank hardware, bolts, and mounting brackets are supplied in high-grade stainless steel (A2/A4 grade) to resist salt-spray atmospheric oxidation.
Absolutely. We regularly build and test transformers filled with synthetic ester (such as Midel 7131) or natural ester (FR3). Ester-filled transformers offer a flash point >300°C (K-class) and complete biodegradability, satisfying UK Environment Agency rules near sensitive waterways.
Every dispatch dossier includes verified Routine Test Reports, Type Test Certificates, Guaranteed Technical Particulars (GTP), GA dimension drawings, schematic wiring diagrams, O&M manuals, and full shipping/customs documentation suitable for UK port clearance.
Standard pole-mounted distribution units (16kVA to 315kVA) are manufactured within 3 to 5 weeks post-drawing approval. Custom power transformers, dry-type units, or specialized sub-station packages require 6 to 9 weeks, with seaworthy freight arranged directly to UK ports.
Speak directly with our senior transformer application engineers to configure custom pole-mounted or ground-mounted transformers tailored to your UK network specifications.