For over four decades, Electrical Supplies Unlimited (ESU) has been a trusted name in San Diego, serving both electricians and homeowners with top-quality electrical components. Our extensive inventory includes new, surplus, and recycled power circuit breakers, panels, and boards, ensuring that our customers have access to a diverse range of options to meet their specific needs. With a commitment to reliability and customer satisfaction, ESU has established itself as a leader in the industry, providing unparalleled service and expertise to our valued clients. Whether you're a seasoned electrician or a homeowner embarking on a DIY project, you can count on ESU to deliver the quality products and knowledgeable support you need to get the job done right.

At Electrical Supplies Unlimited (ESU), our dedication to excellence spans over four decades, making us the go-to destination for electrical supplies in San Diego. As a trusted supplier, we understand the importance of offering a comprehensive selection of new, surplus, and recycled power circuit breakers, panels, and boards to meet the diverse needs of our customers. Whether you're tackling a commercial project or a home renovation, ESU has the expertise and inventory to support you every step of the way. With a legacy built on reliability and customer satisfaction, we take pride in our role as a trusted partner for electricians and homeowners alike. Experience the ESU difference and discover why we've been the preferred choice for electrical supplies in San Diego for over 40 years.

circuit breaker tranformers miramar san diegoESU buys and sells new & used Circuit Breakers, Fuses, Switches, Plugs and more for Linda Vista, San Diego

Electrical Supplies Unlimited buys and sells new & used Circuit Breakers in Linda Vista and San Diego surrounding areas including , Mira Mesa, La Jolla, Pacific Beach, Miramar, University City, Sorrento Valley and many more. Of course, we can arrange shipment on a wide variety of products to service those outside our area. We will also buy your used Transformers.

Electrical Supplies Unlimited (ESU) is your trusted partner for all your electrical supply needs in the Linda Vista area of San Diego. We stand as a premier buyer of a wide range of electrical components, including transformers, breakers, fuses, and more – both new and used. Our commitment to excellence extends to every aspect of our business, ensuring that we provide the highest quality products to our customers. Whether you're looking to sell surplus electrical equipment or searching for specific components, ESU is here to streamline the process, offering competitive pricing and a seamless experience. With a reputation built on reliability and a dedication to customer satisfaction, ESU is the go-to source for all your electrical supply requirements in Bay Ho and beyond. Contact us today to explore how we can assist you with your electrical supply needs

Welcome to ESU, your trusted partner for all your circuit breaker needs in Linda Vista, San Diego. We specialize in buying new, used, and surplus circuit breakers, providing a streamlined solution for individuals and businesses looking to optimize their electrical systems. With a focus on sustainability and cost-efficiency, ESU offers a unique opportunity to turn your surplus or unused circuit breakers into value. Our expert team assesses each circuit breaker to ensure it meets our high standards of quality and safety, ensuring you receive a fair and competitive offer. Whether you're upgrading your electrical infrastructure or simply have surplus inventory, ESU is here to provide a hassle-free way to sell your circuit breakers while contributing to a more sustainable future. Contact us today to discover how ESU can help you unlock the potential of your circuit breakers.

ESU Inc has been in the electrical supply business for over 40 years. We have a large inventory of new, surplus and recycled electrical supplies both for the commercial and residential markets. We are a fully stocked Electrical Distributor and Electrical Wholesaler with many different lines in stock. We specialize in  hard to find items. 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 stock most major brands including General Electric, Hammond Power, ITE Siemens, Cutler Hammer, Square D, FPE Federal Pacific, Pushmatic, Zinsco, Crouse Hinds, Challenger, Westinghouse, Sylvania, and Bryant.

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.

Our Products ESU sells a large and diverse inventory of Electrical Supplies, Electrical Equipment, including Circuit Breakers, Fuses, Transformers, Panelboard switches, Safety switches, Fuseable switches, Meter Sockets, Motor Controllers, Lighting  Ballasts, Bolt switch and much more. We carrier almost all manufacturers including Zinsco, Pushmatic, FPE Federal Pacific, ITE Siemens,  Cutler Hammer, Lutron, Lithonia,, Square D, Challenger and many more. We serve the San Diego and SD County areas and to many other intra and interstate clients. We sell products to fit any requirement or budget. ESU rents Greenlee Wire Pullers, Conduit benders as well as other electrician tools. Talk directly to one of our specialists, Ed, Scott, Kevin or Chris to find out more. So give us a call today at 858.558.2850 and let us serve you

Circuit Breakers Electrical Supplies Unlimited buys and sells new and used Circuit Breakers and more for Linda Vista, Bay Ho, San Diego County and surrounding areas including Sorrento Valley, La Jolla, Miramar, Miramar, Carmel Valley, University City 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 Transformers.

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.

Circuit Breakers Electrical Supplies Unlimited is your go-to source for Circuit Breaker electrical supplies in San Diego and surrounding areas. We have a large inventory of most brands of circuit breakers including most amperages and voltages. We carry a large variety of manufacturers, including Zinsco, Federal Pacific FPE, Pushmatic, Bulldog, Cutler, Hammer, ITE Siemens, Square D etc. in our San Diego store. We carry most amperages and voltages. Some examples of what we carry:

20 Amp thru 125 amp Zinsco breakers
20 amp through 1200 amp 480 volt Siemens breakers 3 phase and single phase
15 thru 100 amp 120/240 Volt Pushmatic Breakers
15 thru 1200 amp 120/240 and 480V Federal Pacific FPE circuit breakers

We are circuit breakers and electrical hardware experts. Do not hesitate to call us at 858.558.2850 to find out which Circuit Breaker is right for your requirement.

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

 

circuit breaker tranformers miramar san diegoESU buys and sells new & used Circuit Breakers, Fuses, Switches, Plugs and more for Mission Valley, San Diego

Electrical Supplies Unlimited buys and sells new & used Circuit Breakers in Mission Valley and San Diego surrounding areas including , Mira Mesa, La Jolla, Pacific Beach, Miramar, University City, Sorrento Valley and many more. Of course, we can arrange shipment on a wide variety of products to service those outside our area. We will also buy your used Transformers.

Electrical Supplies Unlimited (ESU) is your trusted partner for all your electrical supply needs in the Linda Vista area of San Diego. We stand as a premier buyer of a wide range of electrical components, including transformers, breakers, fuses, and more – both new and used. Our commitment to excellence extends to every aspect of our business, ensuring that we provide the highest quality products to our customers. Whether you're looking to sell surplus electrical equipment or searching for specific components, ESU is here to streamline the process, offering competitive pricing and a seamless experience. With a reputation built on reliability and a dedication to customer satisfaction, ESU is the go-to source for all your electrical supply requirements in Mission Valley and beyond. Contact us today to explore how we can assist you with your electrical supply needs

Welcome to ESU, your go-to destination for circuit breaker solutions in Mission Valley, San Diego. At ESU, we're dedicated to simplifying the process of buying new, used, and surplus circuit breakers, catering to a wide range of needs for both residential and commercial applications. If you find yourself with excess circuit breakers due to upgrades or changes in your electrical system, ESU offers a convenient and environmentally-conscious solution. Our team of experts meticulously evaluates each circuit breaker to ensure its quality and performance, offering a competitive price for your surplus inventory. With a commitment to sustainability and efficient electrical solutions, ESU not only helps you maximize the value of your unused circuit breakers but also contributes to responsible resource management. Reach out to ESU today and let us help you turn your surplus circuit breakers into a valuable asset.


ESU Inc has been in the electrical supply business for over 40 years. We have a large inventory of new, surplus and recycled electrical supplies both for the commercial and residential markets. We are a fully stocked Electrical Distributor and Electrical Wholesaler with many different lines in stock. We specialize in  hard to find items. 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 stock most major brands including General Electric, Hammond Power, ITE Siemens, Cutler Hammer, Square D, FPE Federal Pacific, Pushmatic, Zinsco, Crouse Hinds, Challenger, Westinghouse, Sylvania, and Bryant.

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.

Our Products ESU sells a large and diverse inventory of Electrical Supplies, Electrical Equipment, including Circuit Breakers, Fuses, Transformers, Panelboard switches, Safety switches, Fuseable switches, Meter Sockets, Motor Controllers, Lighting  Ballasts, Bolt switch and much more. We carrier almost all manufacturers including Zinsco, Pushmatic, FPE Federal Pacific, ITE Siemens,  Cutler Hammer, Lutron, Lithonia,, Square D, Challenger and many more. We serve the San Diego and SD County areas and to many other intra and interstate clients. We sell products to fit any requirement or budget. ESU rents Greenlee Wire Pullers, Conduit benders as well as other electrician tools. Talk directly to one of our specialists, Ed, Scott, Kevin or Chris to find out more. So give us a call today at 858.558.2850 and let us serve you

Circuit Breakers Electrical Supplies Unlimited buys and sells new and used Circuit Breakers and more for Mission Valley, Bay Ho, San Diego County and surrounding areas including Sorrento Valley, La Jolla, Miramar, Miramar, Carmel Valley, University City 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 Transformers.

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.

Circuit Breakers Electrical Supplies Unlimited is your go-to source for Circuit Breaker electrical supplies in San Diego and surrounding areas. We have a large inventory of most brands of circuit breakers including most amperages and voltages. We carry a large variety of manufacturers, including Zinsco, Federal Pacific FPE, Pushmatic, Bulldog, Cutler, Hammer, ITE Siemens, Square D etc. in our San Diego store. We carry most amperages and voltages. Some examples of what we carry:

20 Amp thru 125 amp Zinsco breakers
20 amp through 1200 amp 480 volt Siemens breakers 3 phase and single phase
15 thru 100 amp 120/240 Volt Pushmatic Breakers
15 thru 1200 amp 120/240 and 480V Federal Pacific FPE circuit breakers

We are circuit breakers and electrical hardware experts. Do not hesitate to call us at 858.558.2850 to find out which Circuit Breaker is right for your requirement.

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

 

circuit breaker tranformers miramar san diegoESU buys and sells new & used Circuit Breakers, Fuses, Switches, Plugs and more for Mission Hills, San Diego

Electrical Supplies Unlimited buys and sells new & used Circuit Breakers in Mission Hills, Mission Valley and San Diego surrounding areas including , Mira Mesa, La Jolla, Pacific Beach, Miramar, University City, Sorrento Valley and many more. Of course, we can arrange shipment on a wide variety of products to service those outside our area. We will also buy your used Transformers.

Welcome to ESU, your go-to destination for circuit breaker solutions in Mission Hills, San Diego. At ESU, we're dedicated to simplifying the process of buying new, used, and surplus circuit breakers, catering to a wide range of needs for both residential and commercial applications. If you find yourself with excess circuit breakers due to upgrades or changes in your electrical system, ESU offers a convenient and environmentally-conscious solution. Our team of experts meticulously evaluates each circuit breaker to ensure its quality and performance, offering a competitive price for your surplus inventory. With a commitment to sustainability and efficient electrical solutions, ESU not only helps you maximize the value of your unused circuit breakers but also contributes to responsible resource management. Reach out to ESU today and let us help you turn your surplus circuit breakers into a valuable asset.

Electrical Supplies Unlimited (ESU) is your trusted partner for all your electrical supply needs in the Mission Hills area of San Diego. We stand as a premier buyer of a wide range of electrical components, including transformers, breakers, fuses, and more – both new and used. Our commitment to excellence extends to every aspect of our business, ensuring that we provide the highest quality products to our customers. Whether you're looking to sell surplus electrical equipment or searching for specific components, ESU is here to streamline the process, offering competitive pricing and a seamless experience. With a reputation built on reliability and a dedication to customer satisfaction, ESU is the go-to source for all your electrical supply requirements in Bay Ho and beyond. Contact us today to explore how we can assist you with your electrical supply needs

ESU Inc has been in the electrical supply business for over 40 years. We have a large inventory of new, surplus and recycled electrical supplies both for the commercial and residential markets. We are a fully stocked Electrical Distributor and Electrical Wholesaler with many different lines in stock. We specialize in  hard to find items. 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 stock most major brands including General Electric, Hammond Power, ITE Siemens, Cutler Hammer, Square D, FPE Federal Pacific, Pushmatic, Zinsco, Crouse Hinds, Challenger, Westinghouse, Sylvania, and Bryant.

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.

Our Products ESU sells a large and diverse inventory of Electrical Supplies, Electrical Equipment, including Circuit Breakers, Fuses, Transformers, Panelboard switches, Safety switches, Fuseable switches, Meter Sockets, Motor Controllers, Lighting  Ballasts, Bolt switch and much more. We carrier almost all manufacturers including Zinsco, Pushmatic, FPE Federal Pacific, ITE Siemens,  Cutler Hammer, Lutron, Lithonia,, Square D, Challenger and many more. We serve the San Diego and SD County areas and to many other intra and interstate clients. We sell products to fit any requirement or budget. ESU rents Greenlee Wire Pullers, Conduit benders as well as other electrician tools. Talk directly to one of our specialists, Ed, Scott, Kevin or Chris to find out more. So give us a call today at 858.558.2850 and let us serve you

Circuit Breakers Electrical Supplies Unlimited buys and sells new and used Circuit Breakers and more for Mission Valley, Bay Ho, San Diego County and surrounding areas including Sorrento Valley, La Jolla, Miramar, Miramar, Carmel Valley, University City 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 Transformers.

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.

Circuit Breakers Electrical Supplies Unlimited is your go-to source for Circuit Breaker electrical supplies in San Diego and surrounding areas. We have a large inventory of most brands of circuit breakers including most amperages and voltages. We carry a large variety of manufacturers, including Zinsco, Federal Pacific FPE, Pushmatic, Bulldog, Cutler, Hammer, ITE Siemens, Square D etc. in our San Diego store. We carry most amperages and voltages. Some examples of what we carry:

20 Amp thru 125 amp Zinsco breakers
20 amp through 1200 amp 480 volt Siemens breakers 3 phase and single phase
15 thru 100 amp 120/240 Volt Pushmatic Breakers
15 thru 1200 amp 120/240 and 480V Federal Pacific FPE circuit breakers

We are circuit breakers and electrical hardware experts. Do not hesitate to call us at 858.558.2850 to find out which Circuit Breaker is right for your requirement.

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

 

circuit breaker tranformers miramar san diegoESU buys and sells new & used Circuit Breakers, Fuses, Switches, Plugs and more for Hillcrest, San Diego

Electrical Supplies Unlimited buys and sells new & used Circuit Breakers in Hillcrest, Mission Hills, Mission Valley and San Diego surrounding areas including , Mira Mesa, La Jolla, Pacific Beach, Miramar, University City, Sorrento Valley and many more. Of course, we can arrange shipment on a wide variety of products to service those outside our area. We will also buy your used Transformers.

Welcome to ESU, your go-to destination for circuit breaker solutions in Hillcrest, San Diego. At ESU, we're dedicated to simplifying the process of buying new, used, and surplus circuit breakers, catering to a wide range of needs for both residential and commercial applications. If you find yourself with excess circuit breakers due to upgrades or changes in your electrical system, ESU offers a convenient and environmentally-conscious solution. Our team of experts meticulously evaluates each circuit breaker to ensure its quality and performance, offering a competitive price for your surplus inventory. With a commitment to sustainability and efficient electrical solutions, ESU not only helps you maximize the value of your unused circuit breakers but also contributes to responsible resource management. Reach out to ESU today and let us help you turn your surplus circuit breakers into a valuable asset.

Electrical Supplies Unlimited (ESU) is your trusted partner for all your electrical supply needs in the Hillcrest area of San Diego. We stand as a premier buyer of a wide range of electrical components, including transformers, breakers, fuses, and more – both new and used. Our commitment to excellence extends to every aspect of our business, ensuring that we provide the highest quality products to our customers. Whether you're looking to sell surplus electrical equipment or searching for specific components, ESU is here to streamline the process, offering competitive pricing and a seamless experience. With a reputation built on reliability and a dedication to customer satisfaction, ESU is the go-to source for all your electrical supply requirements in Bay Ho and beyond. Contact us today to explore how we can assist you with your electrical supply needs

ESU Inc has been in the electrical supply business for over 40 years. We have a large inventory of new, surplus and recycled electrical supplies both for the commercial and residential markets. We are a fully stocked Electrical Distributor and Electrical Wholesaler with many different lines in stock. We specialize in  hard to find items. 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 stock most major brands including General Electric, Hammond Power, ITE Siemens, Cutler Hammer, Square D, FPE Federal Pacific, Pushmatic, Zinsco, Crouse Hinds, Challenger, Westinghouse, Sylvania, and Bryant.

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.

Our Products ESU sells a large and diverse inventory of Electrical Supplies, Electrical Equipment, including Circuit Breakers, Fuses, Transformers, Panelboard switches, Safety switches, Fuseable switches, Meter Sockets, Motor Controllers, Lighting  Ballasts, Bolt switch and much more. We carrier almost all manufacturers including Zinsco, Pushmatic, FPE Federal Pacific, ITE Siemens,  Cutler Hammer, Lutron, Lithonia,, Square D, Challenger and many more. We serve the San Diego and SD County areas and to many other intra and interstate clients. We sell products to fit any requirement or budget. ESU rents Greenlee Wire Pullers, Conduit benders as well as other electrician tools. Talk directly to one of our specialists, Ed, Scott, Kevin or Chris to find out more. So give us a call today at 858.558.2850 and let us serve you

Circuit Breakers Electrical Supplies Unlimited buys and sells new and used Circuit Breakers and more for Hillcrest, San Diego County and surrounding areas including Sorrento Valley, La Jolla, Miramar, Miramar, Carmel Valley, University City 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 Transformers.

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.

Circuit Breakers Electrical Supplies Unlimited is your go-to source for Circuit Breaker electrical supplies in San Diego and surrounding areas. We have a large inventory of most brands of circuit breakers including most amperages and voltages. We carry a large variety of manufacturers, including Zinsco, Federal Pacific FPE, Pushmatic, Bulldog, Cutler, Hammer, ITE Siemens, Square D etc. in our San Diego store. We carry most amperages and voltages. Some examples of what we carry:

20 Amp thru 125 amp Zinsco breakers
20 amp through 1200 amp 480 volt Siemens breakers 3 phase and single phase
15 thru 100 amp 120/240 Volt Pushmatic Breakers
15 thru 1200 amp 120/240 and 480V Federal Pacific FPE circuit breakers

We are circuit breakers and electrical hardware experts. Do not hesitate to call us at 858.558.2850 to find out which Circuit Breaker is right for your requirement.

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

 

circuit breaker tranformers miramar san diegoESU buys and sells new & used Circuit Breakers, Fuses, Switches, Plugs and more for Normal Heights, San Diego

Electrical Supplies Unlimited buys and sells new & used Circuit Breakers inNormal Heights and San Diego surrounding areas including , Mira Mesa, La Jolla, Pacific Beach, Miramar, University City, Sorrento Valley and many more. Of course, we can arrange shipment on a wide variety of products to service those outside our area. We will also buy your used Transformers.

Welcome to ESU, your go-to destination for circuit breaker solutions in Normal Heights, San Diego. At ESU, we're dedicated to simplifying the process of buying new, used, and surplus circuit breakers, catering to a wide range of needs for both residential and commercial applications. If you find yourself with excess circuit breakers due to upgrades or changes in your electrical system, ESU offers a convenient and environmentally-conscious solution. Our team of experts meticulously evaluates each circuit breaker to ensure its quality and performance, offering a competitive price for your surplus inventory. With a commitment to sustainability and efficient electrical solutions, ESU not only helps you maximize the value of your unused circuit breakers but also contributes to responsible resource management. Reach out to ESU today and let us help you turn your surplus circuit breakers into a valuable asset.

Electrical Supplies Unlimited (ESU) is your trusted partner for all your electrical supply needs in the Hillcrest area of San Diego. We stand as a premier buyer of a wide range of electrical components, including transformers, breakers, fuses, and more – both new and used. Our commitment to excellence extends to every aspect of our business, ensuring that we provide the highest quality products to our customers. Whether you're looking to sell surplus electrical equipment or searching for specific components, ESU is here to streamline the process, offering competitive pricing and a seamless experience. With a reputation built on reliability and a dedication to customer satisfaction, ESU is the go-to source for all your electrical supply requirements in Normal Heights and beyond. Contact us today to explore how we can assist you with your electrical supply needs

ESU Inc has been in the electrical supply business for over 40 years. We have a large inventory of new, surplus and recycled electrical supplies both for the commercial and residential markets. We are a fully stocked Electrical Distributor and Electrical Wholesaler with many different lines in stock. We specialize in  hard to find items. 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 stock most major brands including General Electric, Hammond Power, ITE Siemens, Cutler Hammer, Square D, FPE Federal Pacific, Pushmatic, Zinsco, Crouse Hinds, Challenger, Westinghouse, Sylvania, and Bryant.

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.

Our Products ESU sells a large and diverse inventory of Electrical Supplies, Electrical Equipment, including Circuit Breakers, Fuses, Transformers, Panelboard switches, Safety switches, Fuseable switches, Meter Sockets, Motor Controllers, Lighting  Ballasts, Bolt switch and much more. We carrier almost all manufacturers including Zinsco, Pushmatic, FPE Federal Pacific, ITE Siemens,  Cutler Hammer, Lutron, Lithonia,, Square D, Challenger and many more. We serve the San Diego and SD County areas and to many other intra and interstate clients. We sell products to fit any requirement or budget. ESU rents Greenlee Wire Pullers, Conduit benders as well as other electrician tools. Talk directly to one of our specialists, Ed, Scott, Kevin or Chris to find out more. So give us a call today at 858.558.2850 and let us serve you

Circuit Breakers Electrical Supplies Unlimited buys and sells new and used Circuit Breakers and more for Normal Heights, San Diego County and surrounding areas including Sorrento Valley, La Jolla, Miramar, Miramar, Carmel Valley, University City 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 Transformers.

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.

Circuit Breakers Electrical Supplies Unlimited is your go-to source for Circuit Breaker electrical supplies in San Diego and surrounding areas. We have a large inventory of most brands of circuit breakers including most amperages and voltages. We carry a large variety of manufacturers, including Zinsco, Federal Pacific FPE, Pushmatic, Bulldog, Cutler, Hammer, ITE Siemens, Square D etc. in our San Diego store. We carry most amperages and voltages. Some examples of what we carry:

20 Amp thru 125 amp Zinsco breakers
20 amp through 1200 amp 480 volt Siemens breakers 3 phase and single phase
15 thru 100 amp 120/240 Volt Pushmatic Breakers
15 thru 1200 amp 120/240 and 480V Federal Pacific FPE circuit breakers

We are circuit breakers and electrical hardware experts. Do not hesitate to call us at 858.558.2850 to find out which Circuit Breaker is right for your requirement.

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

 

cutler-hammer-circuit-breaker-50

ESU will purchase your excess electrical inventory including Cutler Hammer 50A breakers. We buy and sell most circuit breakers, transformers, new and used and fuses. 

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.

Featured Breaker: Cutler Hammer 50A Industrial Circuit Breaker

 

Manufacturer: Cutler Hammer 

Industrial Circuit Breaker

50A

600V max 250V c.d. Max

Cat. FD3050L

Suitable for use on

Single Phase AC circuits

 

 

Welcome to Electrical Supplies Unlimited, your premier source for used and surplus Cutler Hammer Circuit Breakers across San Diego, Orange, and Riverside Counties. With over 40 years of experience in the industry, we have built a solid reputation for reliability, expertise, and customer satisfaction. Our extensive inventory includes a wide range of high-quality Cutler Hammer Circuit Breakers, ensuring that you find the perfect fit for your electrical needs. Whether you're managing a large commercial project or a small residential upgrade, Electrical Supplies Unlimited provides top-tier products at competitive prices, backed by decades of industry knowledge and exceptional service.

At Electrical Supplies Unlimited, we are dedicated to providing sustainable solutions by buying used and surplus Cutler Hammer Circuit Breakers. This initiative not only supports eco-friendly practices but also offers our clients affordable options without compromising on quality. Our commitment to excellence and customer service has made us a trusted name in the electrical supplies industry throughout San Diego, Orange, and Riverside Counties. Explore our vast selection and experience the convenience and reliability that come with partnering with a company that has been a cornerstone of the community for over four decades. Trust Electrical Supplies Unlimited for all your electrical supply needs and benefit from our unmatched expertise and dedication.

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 or request a quote here!

siemens circuit breakerESU carries a wide stock of Siemens Circuit Breakers for ITE Breaker replacements. We have everything from a single pole 15A 120/240 through 3 pole 3000 Amp 600V in the Siemens ITE line. Siemens makes new circuit breakers that can replace the old ITE breakers. The new Siemens breakers will either have the same ITE part number, or its own Siemens part number.

Siemens Corporation is a U.S. subsidiary of Siemens AG, a global powerhouse in electronics and electrical engineering, operating in the industry, energy, healthcare, and infrastructure & cities sectors. For more than 165 years, Siemens has built a reputation for leading-edge innovation and the quality of its products, services and solutions.

 

Siemens and ITE

In 1983 Siemens bought ITE (formerly known as Gould), a large electrical distribution company, so if you're looking to replace an ITE product, chances are you'll find exactly what you need from Siemens.  

Despite the fact they're now, technically, Siemens breakers, many loyal customers still refer to them by the ITE name.

Are you an electrician or homeowner searching for a reliable source of electrical supplies, specifically ITE breakers? Look no further than Electrical Supplies Unlimited (ESU). As a trusted provider, ESU specializes in buying, selling, and stocking a diverse range of electrical components, including Siemens Circuit Breakers ideal for ITE breaker replacements. With a wide inventory of new, surplus, and recycled items, ESU ensures that both professionals and homeowners have access to high-quality products at competitive prices. Whether you're upgrading your home's electrical system or completing a commercial project, trust ESU to provide the ITE breakers you need for reliable performance and safety. 

 

People also ask
Are ITE and Siemens breakers the same?

 Despite the fact they're now, technically, Siemens breakers, many loyal customers still refer to them by the ITE name

Circuit Breaker Panelboard

ESU will purchase your excess electrical inventory including Electrical Panelboards. We buy most circuit breakers, transformers, new and used and fuses. 

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.

For over 40 years, Electrical Supplies Unlimited has been the go-to destination for buying used and surplus electrical supplies in San Diego, Orange, and Riverside Counties. Specializing in a wide array of electrical components, the company is known for acquiring panel boards, distribution boards, and breaker boxes.

Their extensive experience in the industry ensures that customers receive high-quality, reliable electrical supplies, whether they are looking for circuit breaker panels or other essential components. Electrical Supplies Unlimited's commitment to quality and customer satisfaction has solidified its reputation as a trusted name in the electrical supply market. ,p> Electrical Supplies Unlimited takes pride in its robust inventory and exceptional service, catering to the diverse needs of businesses and contractors across Southern California. The company not only buys but also offers a wide selection of electrical supplies, including used and surplus switchgear, load centers, and control panels. By providing top-tier products and personalized service, Electrical Supplies Unlimited has established itself as a leader in the electrical supply industry. Their longevity and expertise make them a preferred choice for those seeking dependable electrical solutions in San Diego, Orange, and Riverside Counties. Visit Electrical Supplies Unlimited to explore their extensive range of products and experience their unmatched service.  

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 or request a quote here!

circuit breaker

Pushmatic Circuit Breakers are in stock at ESU. We have single pole 15Amp - 40Amp and 2 pole 15Amp-100A all 120/240 double-pole circuit breakers that fit Pushmatic® load centers. It operates at 120/240 VAC.

At Electrical Supplies Unlimited, we pride ourselves on our vast inventory and exceptional service. Our decades-long presence in the market is a testament to our dedication to quality and customer care. We understand the challenges of finding obsolete or rare electrical parts, which is why we offer a wide range of products, from used to surplus, to meet your unique requirements. Whether you’re looking for Pushmatic Circuit Breakers or other hard-to-find items, our knowledgeable team is here to assist you every step of the way. Trust Electrical Supplies Unlimited for all your electrical supply needs across San Diego, Orange, and Riverside Counties, and experience the difference that over 40 years of expertise can make.

For electricians and homeowners seeking reliable sources for Pushmatic Circuit Breakers, look no further than Electrical Supplies Unlimited (ESU). At ESU, we cater to your electrical supply needs by offering a comprehensive range of Pushmatic Circuit Breakers, including new, surplus, and recycled options. Our extensive inventory includes single pole 15Amp - 40Amp and 2 pole 15Amp-100A circuit breakers, all designed to fit Pushmatic® load centers seamlessly. Whether you're in need of replacements for maintenance or upgrades for your electrical system, ESU has you covered. Rest assured, our Pushmatic Circuit Breakers operate at 120/240 VAC, ensuring compatibility with various residential and commercial applications. Trust ESU to provide top-quality Pushmatic Circuit Breakers that meet your requirements while offering reliability and affordability.

Electrical Supplies Unlimited is the trusted source for a comprehensive range of electrical supplies, including new and used Pushmatic Circuit Breakers, serving electricians and electrician companies in the vibrant San Diego area. With a legacy of reliability spanning years, we have established ourselves as a go-to partner for professionals seeking top-quality electrical components. Our commitment to providing a wide array of options, including trusted brands like Pushmatic, ensures that you have the choices you need for your projects. We understand that efficiency, reliability, and cost-effectiveness are paramount in the electrical industry, which is why we offer both new and used circuit breakers to cater to a range of budgets and needs. At Electrical Supplies Unlimited, your electrical projects are in capable hands, and we take pride in being your one-stop destination for all your electrical supply needs in San Diego. Our unwavering dedication to customer satisfaction drives us to go the extra mile in providing exceptional service to electricians and electrician companies in San Diego. We recognize the unique demands of the electrical industry, and that's why we ensure our inventory is stocked with a wide variety of electrical supplies, including Pushmatic Circuit Breakers, to meet your specific requirements. Whether you're working on a residential, commercial, or industrial project, we have the supplies you need to get the job done efficiently and safely. Plus, our offering of used circuit breakers is not only budget-friendly but also eco-conscious, promoting sustainability through reuse. When you choose Electrical Supplies Unlimited, you're not just selecting a supplier; you're partnering with a team committed to your success. Discover the ease and reliability of working with us and experience the convenience of having a trusted electrical supply partner in the heart of San Diego.

square-d-circuit-breaker Square D Electrical Supplies manufacture Breakers, Switchgear, Contactors and Motor Starters.  As one of the largest electrical manufacturers ESU carries a large and diverse inventory of Square D products, including  Circuit Breakers, Transformers, Meter Sections, Disconnects, Panel Board Switches, Switchgear, Contactors and Motor Starters. 

Electrical Supplies Unlimited is your trusted source for a wide range of electrical supplies, serving the needs of electricians and electrical companies throughout San Diego. Our commitment to delivering top-notch products and exceptional service sets us apart in the industry. Whether you're working on a commercial or residential project, our extensive inventory includes new and used Square D circuit breakers and a variety of other electrical supplies that meet the highest quality standards. We understand the importance of reliable electrical components in ensuring the safety and efficiency of any electrical system. That's why we take pride in offering products from reputable brands like Square D, known for their durability and performance. At Electrical Supplies Unlimited, we are dedicated to being your go-to partner, providing the essential tools and equipment that electricians rely on to get the job done right. Contact one of our representatives today at 858.558.2850 to find out more!

Our team at Electrical Supplies Unlimited is committed to making your electrical projects a success. With over 40 years of experience, we know how to get the job done. We understand that electricians and electrical companies demand efficiency, affordability, and quality in their supplies, and we deliver on all fronts. Our selection of Square D circuit breakers, alongside our comprehensive range of electrical products, ensures that you have access to the best tools in the trade. Whether you're looking for new components to keep up with the latest industry standards or seeking cost-effective solutions with our used options, we have you covered. When you choose Electrical Supplies Unlimited, you're choosing a partner that understands your needs and is dedicated to your success. Join our satisfied customer base in San Diego and experience the difference of working with a reliable and customer-focused electrical supplies provider.

Square D is an American manufacturer of equipment used to control and distribute electric power. They are headquartered in Palatine, Illinois.

Square D was founded in 1903 in Detroit, Michigan by Bryson Dexter Horton who is credited with the invention of the safety switch which encased high voltage switches and started the company's main line of business of circuit breakers and encased control panels.

We carry a large and diverse inventory of Square D products, including  Circuit Breakers, Transformers, Meter Sections, Disconnects, Panel Board Switches, Switchgear, Contactors and Motor Starters. Contact one of our representatives today at 858.558.2850 to find out more!

 

Need help replacing FPE Stab-lok Circuit Breakers?

If your home was built between 1950 and 1990 and is equipped with a Federal Pacific Electric (FPE) circuit breaker panel with Stab-Lok circuit breakers, you run a significant risk of breaker malfunction and fire.

The breakers inside the panel are designed to guard your home against serious electrical problems by preventing circuit overload, short circuits and outside power surges coming into the panel. When an overload occurs, a breaker protects you by tripping, thus shutting down the power to the circuit. However, if a breaker is defective or not operating properly, the risk of fire to the panel and consequently to your home becomes imminent.

Why are Federal Pacific breaker boxes dangerous?

Multiple tests done on the breakers since the 1980s have proven that one in four Stab-Lok breakers are defective and will not properly trip off. Unfortunately, when the testing began in the early 1980s, a New Jersey court later ruled that FPE committed testing fraud and a cover-up, labeling the breakers as meeting the standards set by the UL when in reality, they were defective.

In 1983, the Consumer Product Safety Commission closed its two-year investigation and felt it impossible to create a product recall at the time because of budget issues, even as Federal Pacific panels and breakers continued to be installed in millions of homes that to this day still run the risk of an electrical fire. An estimated 2,800 fires each year directly result from Federal Pacific panel breaker malfunction. Federal Pacific Electric has been out of business for many years, but the danger and damage caused by their negligence continues.

Do you have a Federal Pacific panel?

If you own a home between 25 and 65 years old, check your breaker box. A Federal Pacific panel will usually have its name or logo on the front cover. Inside, you will find the name Stab-Lok printed near the center or side of the panel. The intact breakers will have the signature red strip that runs across the front.

If you find you a Federal Pacific panel or Stab-Lok breakers, or are not sure, call ESU, Inc. for further information about replacing your circuit breaker panel.

ESU buys, sells and stocks Eaton Circuit Breakers

square-d-circuit-breaker Eaton Cutler-Hammer offers quality power management solutions for professionals in the aerospace, hydraulics, electrical, automotive, filtration and industrial sectors.

Looking for a reliable source for Eaton electrical supplies? Look no further than Electrical Supplies Unlimited (ESU). ESU has been in business for over 40 years serving San Diego, Orange County and Riverside. Whether you're an electrician working on a project or a homeowner tackling a DIY endeavor, ESU is your go-to destination for all your electrical needs. Specializing in Eaton Cutler Hammer Circuit Breakers, ESU offers a comprehensive range of new, surplus, and recycled options to suit every requirement. From single pole 15A 120/240V breakers to 3 pole 3000Amp 600V models, we've got you covered with the full Eaton line. Trust ESU for quality products, competitive pricing, and exceptional customer service. Shop with confidence and experience the convenience of finding everything you need in one place at Electrical Supplies Unlimited.

Key solutions from Eaton Cutler-Hammer include Industrial Control for NEMA starters and contactors, NEMA pushbutton switches, terminal blocks, relays and circuit breakers. Eaton Cutler-Hammer offers photoelectric and proximity sensors, limit switches, PLCs, HMIs, ethernet connectivity, IEC and NEMA contactors, power supplies, 22mm IEC and 30mm NEMA pushbuttons & tactile switches, toggle switches, thermal magnetic circuit breakers, rocker switches, panel meters, counters, timers and other panel instrumentation.

Electrical Supplies Unlimited is your trusted partner in San Diego for all your electrical needs. Specializing in providing top-quality new and used Eaton Circuit Breakers, we cater to electricians and electrician companies with a commitment to quality and affordability. Our extensive inventory of electrical supplies ensures that you have access to the right components for your projects, whether you're working on residential, commercial, or industrial installations. What sets us apart is our dedication to delivering not just products, but solutions – our team of experts is always ready to assist you in finding the precise Eaton Circuit Breaker or other electrical supplies you require. At Electrical Supplies Unlimited, we understand the importance of reliability and efficiency in the electrical field, and we're here to provide you with the tools you need to excel in your work.

As a trusted source of electrical supplies in San Diego, Electrical Supplies Unlimited takes pride in offering competitive prices and personalized service. Our range of products extends beyond Eaton Circuit Breakers to encompass a comprehensive selection of electrical components, ensuring that you have everything you need for a successful project. Whether you're a seasoned electrician or part of an electrical company, we recognize that time is of the essence. That's why we focus on efficiency and responsiveness, striving to meet your requirements promptly and with the utmost professionalism. When it comes to powering your projects, trust Electrical Supplies Unlimited to provide the quality and service that electricians in San Diego have come to rely on. Explore our wide range of electrical supplies today and experience excellence in every connection.

ESU is the Cutler Hammer Circuit Breakers supply company for San Diego Electricians

cutler hammer circuit breakerWe have everything from a single pole 15A 120/240V through 3 pole 3000Amp 600V in the Cutler Hammer line.

 Electrical Supplies Unlimited, known as ESU, is your trusted partner for top-quality electrical components in San Diego. With a steadfast commitment to excellence, we cater to the needs of electricians and electrical companies by providing a comprehensive range of electrical supplies, including the highly regarded Cutler Hammer Circuit Breakers. Our inventory is carefully curated to meet the demands of various electrical projects, ensuring that professionals have access to reliable components that ensure safety and performance. At ESU, we understand that the success of electrical projects depends on the quality of the supplies used. That's why we prioritize not only providing products like Cutler Hammer Circuit Breakers but also offering exceptional customer service to assist electricians in finding the right solutions for their specific needs. Whether you're working on residential, commercial, or industrial projects, ESU is your one-stop destination for superior electrical supplies that help you get the job done efficiently and safely. As an established player in the San Diego electrical supplies market, ESU takes pride in being a trusted source for electricians and electrical companies. Our extensive inventory includes a wide range of products, from circuit breakers and wiring devices to lighting solutions and more. Cutler Hammer Circuit Breakers, known for their reliability and performance, are just one example of the top-tier brands we carry. What sets us apart is our unwavering dedication to customer satisfaction. Our experienced team is well-equipped to assist you in selecting the right electrical supplies that align with your project requirements and budget. Whether you're in need of specific components, advice, or assistance in navigating the intricacies of electrical systems, ESU is your go-to partner for excellence in both products and service. Explore our vast selection today and experience the ESU difference – where quality, expertise, and reliability come together to power your electrical projects to success.

Are you an electrician or a homeowner in need of reliable electrical supplies? Look no further than Electrical Supplies Unlimited (ESU). As a trusted provider, ESU offers a wide range of electrical products to meet your needs, including new, surplus, and recycled Cutler Hammer Circuit Breakers. Whether you're working on a residential or commercial project, ESU has you covered with a comprehensive selection of Cutler Hammer Circuit Breakers, ranging from single pole 15A 120/240V to 3 pole 3000Amp 600V options. With ESU's commitment to quality and reliability, you can trust that you're getting top-notch products at competitive prices. Visit ESU today to find the perfect Cutler Hammer Circuit Breakers for your electrical projects.

When it comes to electrical supplies, trust the experts at Electrical Supplies Unlimited (ESU) to meet all your needs. ESU specializes in buying, selling, and stocking Cutler Hammer Circuit Breakers, offering a diverse range of options to suit every project requirement. Whether you're looking for single pole 15A 120/240V breakers or 3 pole 3000Amp 600V models, ESU has the inventory to fulfill your needs. With a focus on quality and customer satisfaction, ESU ensures that you get reliable Cutler Hammer Circuit Breakers at competitive prices. Don't compromise on safety and reliability—choose ESU for all your electrical supply needs and experience unparalleled service and product excellence.

The Cutler Hammer Story

Harry Henderson Cutler and Edward West Hammer incorporate the Cutler-Hammer Manufacturing Co. in 1893, specializing in electric starters, speed regulators and field rheostats. Developed first automatic motor starter patented by Cutler in 1900, laying the foundation for the modern motor control industry, and in 1901 the company designed the control equipment for the Panama Canal.    By the 1930s, engineers at Cutler-Hammer had obtained 28 patents for the use of vacuum tubes to control heavy currents. Cutler-Hammer became part of Eaton Corporation in 1978 bringing over $500 million in sales of a complete portfolio of power control and switching devices

 

FEATURED CUTLER HAMMER CIRCUIT BREAKER:

 

cutler-hammer-circuit-breaker-50

ESU will purchase your excess electrical inventory including Cutler Hammer 50A breakers. We buy and sell most circuit breakers, transformers, new and used and fuses. 

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.

Featured Breaker: Cutler Hammer 50A Industrial Circuit Breaker

 

Manufacturer: Cutler Hammer 

Industrial Circuit Breaker

50A

600V max 250V c.d. Max

Cat. FD3050L

Suitable for use on

Single Phase AC circuits

 

 

We have been in the electrical supply business for over 30 years and offer fair prices for your excess electrical inventory. Call us today to find out more or request a quote here!

ITE Siemens Circuit Breakers at ESU for San Diego, Orange County and Riverside

siemens circuit breakerFor over 40 years, ESU has carried a wide stock of ITE Siemens Circuit Breaekrs. We have everything from a single pole 15A 120/240 through 3 pole 3000 Amp 600V in the ITE Siemes line.

Are you an electrician or a homeowner in search of reliable electrical supplies for your project? Look no further than Electrical Supplies Unlimited (ESU). Specializing in ITE Siemens Circuit Breakers, ESU is your go-to source for buying, selling, and stocking new, surplus, and recycled breakers. With a wide inventory ranging from single pole 15A 120/240 breakers to 3 pole 3000 Amp 600V options, ESU has everything you need to ensure your electrical systems operate smoothly and safely. Our commitment to quality and customer satisfaction means you can trust ESU to provide top-notch ITE Siemens Circuit Breakers that meet your specific requirements. Whether you're a professional electrician or a homeowner tackling a DIY project, count on ESU to supply you with the right breakers to get the job done efficiently.

 Electrical Supplies Unlimited is your trusted source for a wide range of electrical supplies, catering to the needs of electricians and electrical companies throughout San Diego, Riverside and Orange county. With 40 years of experience, you know ESU will supply you with a quality fully tested product.  With a special focus on quality and affordability, we pride ourselves on supplying both new and used ITE Siemens Circuit Breakers, among a plethora of other essential electrical components. Our commitment to providing top-notch products ensures that our clients can rely on us for all their electrical project requirements. Whether you're a seasoned electrician or a budding professional, Electrical Supplies Unlimited is your one-stop destination for high-quality supplies that meet industry standards while offering competitive pricing. What sets Electrical Supplies Unlimited apart is our dedication to offering used

ITE Siemens Circuit Breakers, an economical yet reliable solution that fits within various budgets without compromising on safety or performance. Our vast inventory extends beyond circuit breakers to include a comprehensive range of electrical supplies, ensuring that we are a one-click resource for electricians. Backed by a team of experts who understand the unique demands of the industry, we are committed to providing exceptional customer service, technical support, and prompt delivery to keep your projects running smoothly. With Electrical Supplies Unlimited as your trusted partner, you can confidently tackle electrical tasks, knowing that you have access to top-quality supplies in San Diego.

 Electrical Supplies Unlimited (ESU) is your ultimate destination for ITE Siemens Circuit Breakers. Whether you're buying, selling, or stocking breakers for your project, ESU has you covered with a comprehensive inventory of new, surplus, and recycled options. From single pole 15A 120/240 breakers to 3 pole 3000 Amp 600V models, ESU carries a wide range of ITE Siemens Circuit Breakers to suit various applications. With our commitment to quality and extensive stock availability, you can trust ESU to provide the right breakers for your specific needs. Don't settle for subpar electrical supplies – choose ESU for top-notch ITE Siemens Circuit Breakers that deliver reliable performance and peace of mind.

Siemens Corporation is a U.S. subsidiary of Siemens AG, a global powerhouse in electronics and electrical engineering, operating in the industry, energy, healthcare, and infrastructure & cities sectors. For more than 165 years, Siemens has built a reputation for leading-edge innovation and the quality of its products, services and solutions.

The simplest circuit protection device is the fuse. A fuse is just a thin wire, enclosed in a casing, that plugs into the circuit. When a circuit is closed, all charge flows through the fuse wire -- the fuse experiences the same current as any other point along the circuit. The fuse is designed to disintegrate when it heats up above a certain level -- if the current climbs too high, it burns up the wire. Destroying the fuse opens the circuit before the excess current can damage the building wiring.

The problem with fuses is they only work once. Every time you blow a fuse, you have to replace it with a new one. A circuit breaker does the same thing as a fuse -- it opens a circuit as soon as current climbs to unsafe levels -- but you can use it over and over again.

The basic circuit breaker consists of a simple switch, connected to either a bimetallic strip or an electromagnet. The diagram below shows a typical electromagnet design.
 

Circuit breakers are electrical switches designed to protect an electrical circuit from damage caused by overload or short circuit.
If a circumstance arises where a fault condition occurs, the switch discontinues electrical flow. This circuit breaker can be reset either manually or automatically. In contrast, a fuse must be replaced when it operates one time.

Circuit breakers are made in varying sizes, from small devices that protect an individual household appliance up to large switchgear
designed to protect high voltage circuits feeding an entire city.

Types of Circuit Breakers

Low voltage circuit breakers
Magnetic circuit breakers
Thermal magnetic circuit breakers
Common trip breakers
Medium-voltage circuit breakers
High-voltage circuit breakers

Operation

All circuit breakers have common features in their operation, although details vary substantially depending on the voltage class, current rating and type of the circuit breaker.

The circuit breaker must detect a fault condition; in low-voltage circuit breakers this is usually done within the breaker enclosure. Circuit breakers for large currents or high voltages are usually arranged with pilot devices to sense a fault current and to operate the trip opening mechanism. The trip solenoid that releases the latch is usually energized by a separate battery, although some high-voltage circuit breakers are self-contained with current transformers, protection relays, and an internal control power source.