112.5 kVA Dead Front Transformers-22.86/0.208 kV | USA 2024

Engineered for Safety, Designed for Efficiency – The Ideal Pad-Mounted Solution.

01 General

1.1 Project Description

This unit was shipped to the U.S. in 2024, built as a 112.5 kVA three-phase pad-mounted transformer-nothing oversized, nothing over-complicated, just the kind utilities like to install and forget about. The primary rating is 22.86GrdY/13.2 kV, paired with a 0.48/0.277 kV secondary, so it drops neatly into most commercial and light-industrial distribution networks.

We designed it with an NLTC ±2 × 2.5% tap range and aluminum windings, and the vector group is YNyn0, which fits nicely with typical U.S. grounding practices. So the whole electrical setup matches American system conventions without needing any special adaptation.

And because it’s a pad-mounted design, it ends up in all the usual places-residential communities, retail plazas, schools, hospitals, even small factories and airports. Anywhere a steady, quiet supply point is needed, this type of transformer fits right in.

1.2 Key Features

1. Compact, Low-Profile Footprint

This transformer is built to blend into the site rather than stand out. The enclosure is compact and low in height, so it’s easy to place almost anywhere-right beside a building, near a parking area, or quietly hidden behind some basic landscaping. It gives site planners a lot of freedom, both in layout and in how they want the place to look.

2. Shorter LV Runs, Lower Losses & Lower Cost

Keeping the transformer close to the load makes a noticeable difference. The low-voltage cable run gets much shorter, and on a 112.5 kVA unit (22.86GrdY/13.2 kV → 0.208 kV), that really matters because the LV current is high.
If the cable run were longer, you’d see more I²R losses, larger conductor sizes, higher heat, and a higher installation cost-everything starts to add up fast.

By placing the unit directly where the load is, utilities avoid unnecessary copper or aluminium, reduce voltage drop issues, and maintain overall efficiency in better shape. It’s a simple layout decision that saves more money than most people realise.

3. Sealed, Safe, and Tamper-Resistant

The enclosure is fully sealed and tamper-resistant. No exposed conductors, no open compartments-just a clean, locked-down design. That makes it well-suited for public areas like neighbourhoods, school walkways, parks, and any place where people pass by without giving the equipment a second thought.

1.3 Technical Specification

112.5 KVA transformer specifications type and data sheet

1.4 Drawings

112.5 KVA pad mounted transformer diagram drawing and size.

02 Manufacturing

2.1 Core

The five-post core design features three main and two auxiliary columns, creating a closed magnetic circuit for each phase. This configuration balances the three-phase magnetic paths, significantly reducing flux imbalance and associated additional losses by over 15%. The auxiliary columns act as magnetic shunts, containing flux leakage and lowering total core losses by 10–20%, thereby improving operational efficiency. With robust mechanical stability that withstands short-circuit electromagnetic forces, the design also minimizes core vibration and noise by at least 5 dB through optimized magnetic circuit symmetry, ensuring reliable performance under demanding conditions.

2.2 Winding

Our hybrid foil-and-wire winding system delivers measurable performance gains for industrial and utility applications. By optimizing magnetic symmetry, it reduces stray losses by 15% and contains leakage flux, directly improving efficiency. The LV foil winding withstands short-circuit forces up to 60 kA/3s, while the stabilized HV winding ensures structural reliability. Thermally, the design cuts LV hotspot temperature rise by 10–15°C and maintains partial discharge below 5 pC. This results in extended insulation life, reduced operating costs, and greater resilience for demanding environments like manufacturing plants or coastal substations.

2.3 Tank

The oil tank of our US-style pad-mounted transformer is constructed from 304-grade stainless steel and features a fully sealed, robotically-welded design. This robust construction, combined with a multi-layer coating system including hot-dip galvanization and epoxy spray, ensures long-term structural integrity and corrosion resistance-even in coastal or high-humidity environments. Critical sealing is achieved through nitrile rubber gaskets and continuous welds, maintaining an IP68 rating and preventing moisture ingress that preserves dielectric oil quality. Equipped with a magnetic oil level gauge, pressure relief device, and integrated monitoring points, the tank supports predictive maintenance and delivers a >99.5% sealing reliability rate, minimizing lifecycle costs for utility and industrial clients operating in demanding conditions.

2.4 Final Assembly

The final assembly integrates core components and enclosures in a controlled process: the active part is vacuum-oil-impregnated and sealed within the tank under dew points below -40°C, ensuring structural integrity and eliminating internal moisture. High- and low-voltage compartments are then fitted with type-tested devices-including load-break switches and molded-case circuit breakers-all pre-wired to reduce field connection time by 60%. The fully assembled enclosure, sealed with EPDM gaskets and finished with corrosion-resistant coating, achieves IP68 protection for outdoor operation. Grounding systems are verified to withstand 30 kA/2s fault current, delivering a ready-to-energize unit that minimizes installation time and ensures long-term reliability in harsh environments.

03 Standard Accessories

The transformer comes with a set of standard accessories to ensure safe, reliable, and convenient operation:

Standard Accessories 3 pieces Bayonet Fuse &Current Limit Fuse (CLF) 1 piece Oil Drain Valve 1 piece Pressure Relief Device 1 piece Liquid Level Indicator 1 piece Oil Thermometer 1 piece Vacuum Pressure Gauge 1 piece Drip Tray 6 pieces Parking Stands &Bushing Well

Optional Accessories These optional components enhance operational flexibility and monitoring capabilities: Load Break Inserts Complete with Dust Cap Off-Circuit Tap Changer IFD – Insulating Fault Detector

04 Testing

05 Packing and Shipping

5.1 Packing

The transformer is secured within a reinforced timber crate constructed from ISPM 15-certified treated lumber, with internal bracing designed to withstand stacking loads exceeding 7 metric tons. Critical components are immobilized using shock-absorbing HDPE brackets, reducing vibration-induced damage risk by over 30% during rail transport. The unit undergoes vacuum-sealing with 0.12mm anti-condensation barrier film, maintaining internal humidity below 30% for up to 12 months of outdoor storage. This packaging system, validated through ISTA 3A testing, has achieved a 99.8% damage-free delivery rate across transcontinental logistics, effectively addressing corrosion protection and structural stability concerns for utility clients managing extended supply chains.

5.2 Shipping

The transformer is secured in a 40ft HC container using four-point steel lashing with 3-inch edge protectors, while real-time shock recorders monitor all vertical and horizontal impacts throughout the voyage, ensuring they remain below 2.5g and 1.2g respectively. This method, validated by ISTA 3E testing, has achieved a 99.9% damage-free rate on routes exceeding 8,000 nautical miles. The unit’s internal vacuum sealing and pressurized nitrogen blanket (maintained at 0.15-0.3 bar) prevent moisture ingress during high-humidity ocean transit, ensuring insulation integrity upon arrival. This logistics approach directly supports just-in-time project schedules by eliminating pre-commissioning drying requirements and reducing commissioning time by 48 hours-critical for coastal utility projects with tight outage windows.

06 Site And Summary

Our three-phase pad-mounted transformers form the core of modern power distribution, delivering measurable value through IEEE C57.12.00-compliant designs that achieve >99% efficiency and withstand 65 kA short-circuit currents. Engineered with 304 stainless steel tanks and hybrid foil-wire windings, they provide 25% lower lifecycle costs in coastal or high-load industrial environments. Compact, corrosion-resistant, and pre-equipped for smart grid integration, they enable rapid deployment in urban electrification, renewable energy interconnections, and manufacturing plant expansions-ensuring 30+ years of reliable service with maintenance intervals extended by 40%. To discuss how our transformers can address your specific grid hardening or capacity expansion requirements, contact our engineering team for a technical proposal.