Up to 11,000 kVA & 35 kV
Padmount Transformers
Padmount transformers in stock and ready for same-day shipping.
Excellence Starts Here
- Same-Day Availability
- Fully Customizable
- IEEE/ANSI C57.12
- Small- & Large-Scale Orders
- Free Shipping*Contiguous 48 United States
Your Power, Your Way
Whether you need an immediate transformer solution or hundreds of unique units, we’ll deliver the exact equipment you need—in record time.
IN STOCK
Need A
Solution Fast?
We have 1,000+ customizable transformers—up to 10 MVA/35 kV—in stock and ready to ship, same day.
MADE-TO-ORDER
Need Something
Custom?
Build the exact padmount transformer you need—up to 11 MVA/35 kV—with a 24-week standard lead time (or 16-week, expedited).
Setting A New Industry Standard
We'll provide a quote for all available options, giving you the freedom to choose a solution that encompasses your ideal price, lead time, and equipment configuration.
CORE Padmounts
The Competition
PRICE
LEAD TIME
QUALITY
 | |
|---|---|
Features | Three-Phase Padmount |
 Size & Voltage | 30 kVA–11 MVA Up to 35 kV |
 BIL Rating | Up to 200 kV |
 Cooling Classes | ONAN/ONAF (Mineral Oil) KNAN/KNAF (FR3 Natural Ester) |
 Winding Configurations | Δ (Delta) Y (Wye) GrdY (Grounded Wye) Dual-Voltage |
 Taps & Changers | No Taps (5) 2 Above & 2 Below (7) 4 Above & 2 Below 7-Position J-Tap 5-Position K-Tap Custom Taps |
 Core Materials | Grain Oriented & Laminated Silicon Steel Amorphous Steel |
 Core Design | Three-Legged Five-Legged |
 Coil Material | Aluminum Copper |
 Terminations | Live Front Dead Front, Loop Feed Dead Front, Radial Feed |
 HV Bushings | 200A Wells w/ Inserts 200A One-Piece Purple Cuff 600A Dead Break 900A Dead Break Spades w/ NEMA Hole Spacing |
 LV Bushings | Spade w/ NEMA Hole Spacing |
 Switching | 2 Position LBOR 4 Position LBOR - T Blade 4 Position LBOR - V Blade Switch Contacts |
 Fusing | Bayonet Fuses Weak Links Isolation Links Current-Limiting Fuses (CLFs) |
 Temperature Rise | 55°C 65°C 75°C |
 K-Factor | 1, 4, 9, 13, 20, 30 |
 Features | Taps Mineral Oil / FR3 Live / Dead Front Radial / Loop Feed Drain & Sample Valve Infrared (IR) Window External Accessories |
 Accessories | Infrared (IR) Window External Drain & Sample Pressure Relief Valve Pressure Release Device Sudden Pressure Sensor Motorized LBOR Liquid Temperature Gauge Liquid Level Gauge Gauges w/ Contacts LBOR w/ Contacts Kirk Key Provisions Winding Temperature Gauge Through-Tank Window |
 Build & Test Standards | IEEE/ANSI C57.12, FM Approved |
 Certifications | UL, cUL, DOE2016 |
Shipping & Availability
New (In Stock) | New (Custom) | ProCORE | Refurbished | Rental |
|---|---|---|---|---|
Stock StatusIn Stock | Stock StatusMade-To-Order (MTO) | Stock StatusIn Stock | Stock StatusRefurbished-To-Order | Stock StatusIn Stock |
Lead TimeSame-Day Shipping | Lead TimeSame-Day Shipping | Lead TimeSame-Day Shipping | Lead TimeSame-Day Shipping | Lead TimeSame-Day Shipping |
Price$$$$ | Price$$$ | Price$$$ | Price$$ | Price$ |
Standard Warranty2 Years (Extended up to 5 Years) | Standard Warranty2 Years (Extended up to 5 Years) | Standard Warranty3 Years (Extended up to 5 Years) | Standard Warranty3 Years (Extended up to 5 Years) | – |
Made-to-order padmount transformers
Receive customized equipment in just 24 weeks with our made-to-order (MTO) padmount transformers.
Questions?
We Have Answers.
Does CORE ship internationally? 
We do, and we’d be happy to help coordinate an international shipment. Or, we can facilitate a delivery to your local freight forwarder.
Are emergency and holiday shipments available?
Our normal office hours follow most holidays, but our team is available 24/7/365 for customer emergencies. Please note that orders that have been taken or shipped after hours, on weekends, or on holidays, though, will incur additional emergency fees.
Can I have the transformer painted a different color?
As long as it’s not USC Gamecock Garnet Red (Go Tigers!), we should be able to accommodate. You can talk to one of our sales associates for more info.
Does the free shipping include a dedicated truck?
Our free shipping does not include a dedicated truck. Most transformers are quoted with free delivery anywhere in the lower 48 states, with a few exceptions for extra-large specialty units. These are not dedicated loads, but frequently ship within 24–72 hours of the order receipt.
Can I arrange my own pick-up or drop-off?
Absolutely. Most of our orders include free freight anywhere in the lower 48 states, however, you’re welcome to arrange your own freight. Our team will happily load your truck at no extra cost.
Can specific labels be applied to the unit?
Not a problem. Just be sure to coordinate with your sales associate when placing your order.
Are CORE transformers autobots or decepticons?
If they ever start talking or walking, please submit a warranty claim. For now, they’re 100% focused on uptime and reliability.
What kind of equipment is needed to offload the transformer?
Most padmounts are loaded and unloaded with a forklift, using slings connected to the transformer’s lifting eyes. Feel free to reach out with any additional questions—we can confirm the equipment you’ll need for any specific unit.
Can CORE build to custom dimensions?
Absolutely! We’ve tackled some massive projects and have met some off-the-wall requirements. We’re here to make your life easier. While it’s not a guarantee, we’ll do what we can to help. Give us a call and we’ll see what we can do.
Can I buy extra oil from CORE?
Our goal is to be easy to do business with, and sometimes that means shipping a few totes of mineral, silicone, or FR3 oil. Give your sales associate a call to discuss your options.
Industries We Support
Commercial
Reliable energy distribution for retail, offices, and commercial campuses.
Talk To A Commercial Expert
Industrial
Engineered to meet the demands of heavy-duty industrial operations.
Connect With An Industrial Power Expert
Renewables
Seamless integration for solar, wind, and other renewable energy systems.
Contact A Renewables SpecialistData Centers & Critical Power
High-performance power solutions for data, tech, and mission-critical loads.
Talk To Us About Critical PowerCustomers We Serve
Electrical Contractors
From installations to repairs, we’ll support you with the highest-quality transformer solutions.
Talk To An Expert
Electrical Distributors
Partnering with you in all-things-transformers, so that your clients never have to wait.
Connect With Our Team
NETA / Field Service
When you run into trouble in the field, we’re the number you want to have on speed dial.
Find An Emergency Solution
Operations & Maintenance
We’re available to assist your team 24/7/365 to ensure your division runs smoothly.
Get A Same-Day Response