Welcome to Electrical Supplies Unlimited (ESU Inc), your trusted partner in the electrical supply industry for over four decades. With a rich legacy spanning 40 years, ESU has been a cornerstone for electricians in San Diego, providing top-notch electrical supplies and unparalleled service. Our commitment to excellence and reliability has made us the go-to destination for professionals seeking quality products to power their projects. At ESU, we understand the importance of staying ahead in the ever-evolving electrical landscape. Our extensive inventory caters to the diverse needs of electricians, ensuring they have access to the latest and most advanced equipment. Additionally, we are proud to announce our new initiative – ESU Inc is now actively purchasing excess electrical transformer inventory. If you have surplus transformers, partner with us to turn them into valuable assets. Trust ESU to not only meet your current electrical supply needs but also to provide sustainable solutions for your surplus inventory, reinforcing our commitment to the success of electricians in San Diego and beyond.

ESU will purchase your excess electrical transformer inventory. We buy new and used transformers, single phase, three phase, buck boost and more. We have been in the electrical supply business for over 40 years and offer fair prices for your excess electrical inventory. Call us today to find out more and to get a quote!

Single Phase/Three Phase Transformers: 

A single phase transformer is a type of transformer which operates on single-phase power.  The applications of a single-phase transformer are varied. Some uses:

To step-down long-distance signals to support both residential and light-commercial electronic devices.
To supply power to non-city areas.
To step-up power in home inverters.

It is most commonly used to increase (‘step up’) or decrease (‘step down’) voltage levels between circuits.


Three-phase transformers are a type of transformers that are used to change voltages of electrical systems with three phases. There are different types of configurations for three phase transformers: star-star, delta-delta, star-delta, and delta-star. 

Core-type transformers act as a single-core, three-phase transformers where each phase is magnetically coupled to each other.


Electrical Supplies Unlimited is your company's business source for testing, repairing, rebuilding or reconditioning electrical equipment. ESU maintains a wide variety of out of stock circuit breakers, relays, transformers, switches, relays, motor controls, and other electrical equipment.

power transformerBuying Surplus Used Electric Power Transformers - Single Phase and Three Phase

Electrical Supplies Unlimited buys and sells new and power & electrical Transformers and more for San Diego County and surrounding areas including Orange County, Riverside and more. Of course, we can arrange shipment on a wide variety of products to service those outside our area. We will also purchase your used Electrical Supplies such as Circuit Breakers, Switches, Fuses and more.

ESU Inc has been in the electrical supply business for over 30 years. We have a large inventory of new, surplus and recycled electrical supplies both for the commercial and residential markets so we are constantly purchasing surplus electrical equipment.  We can offer the best pricing on your used and obsolete Electrical Transformers as our large client base allows us to give you the highest price possible. If you have surplus transformer equipment, give us a call and we will give you a quote. We will arrange for pickup and you get payment!

Our staff is very knowledgeable and our mission is to ensure that our customers expectations are exceeded. Ask around, our reputation is what makes us! Or just call to find out yourself at 858.558.2850.

We purchase most major brands including Acme, Westinghouse, Cutler Hammer, ITE Siemens, FPE  Federal Pacific, Square D, General Electric and Zinsco products. We are a fully stocked Electrical Distributor and Electrical Wholesaler with many different lines in stock.

Our inventory consists of a large selection of Circuit Breakers, Transformers, Disconnects, Panelboards to 600v, Fuses up to 3000 Amps, Bolt Switch Pullouts, Motor Starters and Relays, Meter sockets, Lighting ballasts, Metal Halide and Sox bulbs. We also carry Lithonia Commercial and residential lighting fixtures as well.

We are power transformer and electrical hardware experts. Do not hesitate to call us at 858.558.2850 to find out how ESU can help you with your excess Transformer needs.

Your one stop go-to guys. Always at your service!


Surplus Electrical Power Transformer Buyers
Surplus Electrical Power Transformers