Circuit Breakers in Bonita, San Diego. ESU buys and sells new & used Breakers and Panels!
Electrical Supplies Unlimited buys and sells new & used Circuit Breakers in Rancho Del Rey San Diego surrounding areas including Chula Vista, Bonita, Terra Nova, Eastlake Greens, Sunbow 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.
ESU Inc has proudly served the electrical supply industry for more than 40 years. We carry a wide selection of new, surplus, and recycled electrical supplies for both residential and commercial needs. As a fully stocked Electrical Distributor and Wholesaler, we maintain many different product lines on hand. We specialize in locating hard-to-find items, and our experienced staff is committed to going above and beyond customer expectations. Our reputation speaks for itself—just ask around, or give us a call at 858.558.2850 to experience it firsthand.
Our inventory includes most leading brands such as 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, 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 sells and buys both new and used Circuit Breakers, serving Circuit Breakers to Rancho Del Rey, San Diego and nearby areas such as Chula Vista, Bonita, Terra Nova, Eastlake Greens, Sunbow, and more. We can also arrange shipment of many products to serve customers outside the region. In addition, we will purchase your used Transformers, Breakers, Panels and most Electrical Supplies.
We handle most of the major brands, including Westinghouse, Acme, Cutler Hammer, ITE Siemens, Federal Pacific (FPE), Square D, General Electric, and Zinsco. As a fully stocked Electrical Distributor and Wholesaler, we keep many different product lines readily available.
Electrical Supplies Unlimited is San Diego’s go-to source for Circuit Breaker electrical supplies. Our inventory includes a wide range of circuit breakers across most voltages and amperages. In our San Diego store, we carry products from many manufacturers such as Zinsco, Federal Pacific (FPE), Pushmatic, Bulldog, Cutler Hammer, ITE Siemens, Square D, and more. We stock most amperages and voltages. Some examples of what we offer:
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 Breakers in San Diego
Circuit Breakers in San Diego! ESU buys and sells new & used Breakers and Panels!
Electrical Supplies Unlimited buys and sells new & used Circuit Breakers San Diego in San Diego surrounding areas including Hillcrest, Northpark, City Heights, Mission Valley, National City 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.
ESU Inc has proudly served the electrical supply industry for more than 40 years. We carry a wide selection of new, surplus, and recycled electrical supplies for both residential and commercial needs. As a fully stocked Electrical Distributor and Wholesaler, we maintain many different product lines on hand. We specialize in locating hard-to-find items, and our experienced staff is committed to going above and beyond customer expectations. Our reputation speaks for itself—just ask around, or give us a call at 858.558.2850 to experience it firsthand.
Our inventory includes most leading brands such as 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 sells and buys both new and used Circuit Breakers, serving San Diego and nearby areas such as Sorrento Valley, La Jolla, Miramar, Carmel Valley, University City, and more. We can also arrange shipment of many products to serve customers outside the region. In addition, we will purchase your used Transformers.
We handle most of the major brands, including Westinghouse, Acme, Cutler Hammer, ITE Siemens, Federal Pacific (FPE), Square D, General Electric, and Zinsco. As a fully stocked Electrical Distributor and Wholesaler, we keep many different product lines readily available.
Electrical Supplies Unlimited is San Diego’s go-to source for Circuit Breaker electrical supplies. Our inventory includes a wide range of circuit breakers across most voltages and amperages. In our San Diego store, we carry products from many manufacturers such as Zinsco, Federal Pacific (FPE), Pushmatic, Bulldog, Cutler Hammer, ITE Siemens, Square D, and more. We stock most amperages and voltages. Some examples of what we offer:
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
Siemen Circuit Breakers in San Diego
Learn More About Circuit Breakers
Explore our in-depth guides to help you choose the right breaker and maintain a safe electrical system:
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!
How to Replace FPE, Zinsco, and Challenger Circuit Breakers
How to Replace FPE, Zinsco, and Challenger Circuit Breakers
Many older homes still contain electrical panels manufactured by Federal Pacific Electric (FPE), Zinsco, or Challenger. These brands were widely installed between the 1950s and 1980s, but today they are commonly flagged by home inspectors and electricians due to safety concerns and reliability issues.
If your home has one of these panels, it is important to understand the risks and the recommended solutions. In many cases, electricians recommend replacing FPE, Zinsco, or Challenger breakers to improve electrical safety and ensure the system meets modern standards.
Why FPE, Zinsco, and Challenger Breakers Are a Concern
Older circuit breaker designs may not provide the same level of protection as modern breakers. Some of these panels have been associated with breakers that fail to trip during overloads or short circuits. When a breaker fails to shut off power, electrical wiring can overheat and increase the risk of electrical fires.
Because of these concerns, many electricians recommend upgrading or replacing these breakers during electrical panel inspections or home renovations.
Federal Pacific (FPE) Stab-Lok Breakers
Federal Pacific Electric panels using Stab-Lok breakers were installed in millions of homes across the United States. Over time, electrical professionals began raising concerns that certain Stab-Lok breakers may fail to trip under fault conditions.
As a result, many insurance companies and home inspectors recommend replacing or upgrading panels that contain FPE breakers.
Zinsco Electrical Panels
Zinsco panels were popular in residential construction for several decades. However, these breakers have been known to experience issues such as failing to trip or losing proper contact with the panel bus bar.
When this occurs, breakers may overheat or melt, potentially damaging the electrical panel.
Challenger Circuit Breakers
Challenger breakers were used in residential and commercial buildings during the 1970s and 1980s. Some models were later recalled due to concerns related to overheating and electrical failure.
While not all Challenger breakers are unsafe, electricians often recommend upgrading older units to modern circuit protection systems.
Signs Your Electrical Panel May Need Replacement
If your home contains an older electrical panel, watch for these warning signs:
Breakers that trip frequently or fail to reset
Burn marks or discoloration around breakers
A burning smell near the electrical panel
Flickering lights or unstable electrical power
An electrical panel manufactured by FPE, Zinsco, or Challenger
If you notice any of these issues, the electrical system should be inspected by a licensed electrician.
Options for Replacing Unsafe Breakers
In many cases, electricians recommend replacing the entire electrical panel rather than simply replacing individual breakers. Modern panels provide improved circuit protection and are designed to support the electrical demands of today’s homes.
Upgrading the panel may also allow for additional circuits to support new appliances, electric vehicle chargers, or home upgrades.
Modern Circuit Breaker Alternatives
Modern circuit breakers from trusted manufacturers offer improved reliability and safety features such as arc fault and ground fault protection.
Popular modern breaker brands include:
Square D
Eaton
Siemens
General Electric (GE)
Using modern breakers that are designed for your specific electrical panel ensures proper fit, safety certification, and long-term reliability.
Learn More About Circuit Breakers
If you're researching breaker types, brand compatibility, or electrical safety upgrades, explore our complete Circuit Breaker Resource Hub where we provide expert guides to help homeowners, electricians, and contractors choose the right circuit protection equipment.
Learn More About Circuit Breakers
For a complete overview of breaker types, brands, and electrical safety considerations, visit our Circuit Breaker Resource Hub where we provide expert guides for residential, commercial, and industrial electrical systems.
For a complete overview of breaker types, brands, and electrical applications, visit our Circuit Breaker Resource Hub.
Circuit Breakers in National City, San Diego. ESU buys and sells new & used Breakers and Panels!
Electrical Supplies Unlimited buys and sells new & used Circuit Breakers in National City San Diego surrounding areas including Chula Vista, Imperial Beach, Bonita, Rancho Del Rey, Terra Nova, Eastlake Greens 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.
ESU Inc. has proudly served the electrical supply industry for over 40 years. We offer an extensive selection of new, surplus, and recycled electrical supplies to meet both residential and commercial needs. As a fully stocked electrical distributor and wholesaler, we carry a wide range of product lines and specialize in sourcing hard-to-find items. Our knowledgeable team is dedicated to exceeding customer expectations, and our long-standing reputation speaks for itself. Call us at 858.558.2850 to experience our service firsthand.
Our inventory features products from many leading manufacturers, including General Electric, Hammond Power, ITE Siemens, Cutler Hammer, Square D, FPE Federal Pacific, Pushmatic, Zinsco, Crouse-Hinds, Challenger, Westinghouse, Sylvania, and Bryant.
We stock a broad selection of electrical equipment, including circuit breakers, transformers, disconnects, panelboards up to 600V, fuses up to 3000 amps, bolt switch pullouts, motor starters and relays, meter sockets, lighting ballasts, and metal halide and SOX bulbs. ESU also carries Lithonia commercial and residential lighting fixtures.
ESU supplies a diverse range of electrical products to fit virtually any application or budget, serving customers throughout San Diego County as well as intra- and interstate clients. In addition, we rent Greenlee wire pullers, conduit benders, and other professional electrician tools. For personalized assistance, speak directly with one of our specialists—Scott, Kevin, or Chris. Call 858.558.2850 today and let ESU serve your electrical supply needs.
Circuit Breakers Electrical Supplies Unlimited sells and buys both new and used Circuit Breakers, serving Circuit Breakers to National City, San Diego and nearby areas such as Chula Vista, Bonita, Rancho Del Rey, Terra Nova and more. We can also arrange shipment of many products to serve customers outside the region. In addition, we will purchase your used Transformers, Breakers, Panels and most Electrical Supplies.
We handle most of the major brands, including Westinghouse, Acme, Cutler Hammer, ITE Siemens, Federal Pacific (FPE), Square D, General Electric, and Zinsco. As a fully stocked Electrical Distributor and Wholesaler, we keep many different product lines readily available.
Electrical Supplies Unlimited is San Diego’s go-to source for Circuit Breaker electrical supplies. Our inventory includes a wide range of circuit breakers across most voltages and amperages. In our San Diego store, we carry products from many manufacturers such as Zinsco, Federal Pacific (FPE), Pushmatic, Bulldog, Cutler Hammer, ITE Siemens, Square D, and more. We stock most amperages and voltages. Some examples of what we offer:
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!
How To Choose a Circuit Breaker
How to Choose the Right Circuit Breaker
Choosing the right circuit breaker is essential for protecting your electrical system from overloads and short circuits. Whether you are upgrading a residential panel, installing new commercial equipment, or replacing an outdated breaker, understanding how to choose a circuit breaker ensures safety, compliance, and long-term reliability.
This guide explains the key factors electricians and contractors consider when selecting a breaker, including load calculations, voltage ratings, breaker types, and brand compatibility.
Why Selecting the Correct Circuit Breaker Is Important
A circuit breaker protects electrical wiring and connected equipment by automatically shutting off power when a fault or overload occurs. Installing the wrong breaker can lead to nuisance tripping, equipment damage, or serious electrical hazards.
When determining what size circuit breaker you need, you must consider electrical load, wire size, panel compatibility, and application type.
Step 1: Determine the Electrical Load
The first step in choosing a breaker is calculating the electrical load the circuit will carry. Load is measured in amps and represents the amount of electrical current required by connected devices.
As a general rule, electricians size breakers to handle approximately 80% of the circuit's maximum rated capacity to prevent overheating and tripping.
Step 2: Match the Breaker to the Panel Brand
Circuit breakers are designed to work with specific electrical panels. Using the correct brand ensures a safe mechanical connection and proper electrical performance.
Common circuit breaker brands include Square D, Eaton, Siemens, GE, and Cutler Hammer. Always verify compatibility with your panel before purchasing a replacement breaker.
Step 3: Choose the Correct Voltage Rating
Circuit breakers are rated for different voltage levels depending on the application. Most residential systems use low voltage breakers rated for 120V or 240V, while commercial and industrial systems may require medium voltage breakers.
Understanding voltage requirements is an important part of selecting the right circuit breaker for your electrical system.
Step 4: Select the Proper Breaker Type
Different electrical applications require different breaker designs. Some of the most common types include:
Standard thermal magnetic breakers
Ground fault circuit interrupter (GFCI) breakers
Arc fault circuit interrupter (AFCI) breakers
Double-pole breakers for 240V circuits
Each breaker type provides specific protection depending on the environment and electrical equipment being used.
Common Mistakes When Choosing Circuit Breakers
Many property owners attempt to replace breakers without considering compatibility or electrical load requirements. Some common mistakes include installing an oversized breaker, using incompatible brands, or ignoring wiring limitations.
These mistakes can create serious safety risks and may violate electrical code requirements.
Find the Right Circuit Breaker for Your System
Whether you're replacing a failed breaker or designing a new electrical installation, choosing the correct breaker is essential for safety and performance.
For a complete overview of breaker types, brands, and electrical applications, visit our Circuit Breaker Resource Hub.
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, 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 in San Diego! ESU buys and sells new & used Breakers and Panels!
Why FPE, Zinsco, and Challenger Breakers Are a Concern