Circuit Breakers Golden Triangle San Diego – New & Used Breakers, Panels & Electrical Supplies

Electrical Supplies Unlimited (ESU) is your trusted source for Circuit Breakers in the Golden Triangle are of San Diego, serving contractors, electricians, property managers, and homeowners throughout the Golden Traingle area and surrounding communities including University City, Hillcrest, Golden Hill, Bankers Hill, and greater San Diego County.

We buy and sell both new and used circuit breakers, electrical panels, transformers, and electrical equipment. Whether you need replacement breakers, obsolete breakers, or hard-to-find electrical components, ESU provides dependable solutions backed by over 40 years of industry experience.

San Diego’s Trusted Circuit Breaker Supplier Since 1985

ESU has proudly served the San Diego electrical supply industry for more than four decades. As a fully stocked electrical distributor and wholesaler, we carry a wide range of residential, commercial, and industrial electrical supplies designed to meet virtually any project requirement.

Our experienced team specializes in locating discontinued, surplus, and specialty electrical products, helping customers source reliable solutions quickly and efficiently.

Leading Circuit Breaker Brands Available

Our extensive inventory includes major circuit breaker manufacturers and trusted industry brands, including:

General Electric (GE), Siemens / ITE, Cutler Hammer, Square D, Federal Pacific (FPE), Pushmatic, Zinsco, Challenger, Bryant, Westinghouse, Sylvania, Crouse Hinds, Bulldog, and many more.

Complete Electrical Supply Inventory

In addition to circuit breakers, ESU stocks a large inventory of:

• Transformers
• Panelboards up to 600V
• Disconnects & Safety Switches
• Fuses up to 3000 Amps
• Meter Sockets
• Motor Starters & Relays
• Lighting Ballasts & Fixtures
• Bolt Switch Pullouts
• Commercial & Residential Electrical Supplies

We also offer Greenlee tool rentals, conduit benders, wire pullers, and additional electrician equipment for contractors throughout San Diego County.

Specialists in New, Used & Obsolete Circuit Breakers

ESU is San Diego’s go-to source for new, used, surplus, and obsolete circuit breakers. We carry a broad range of amperages and voltages for nearly every major electrical system.

Examples of our inventory include:

• 20 Amp to 125 Amp Zinsco breakers
• 15 Amp to 100 Amp Pushmatic breakers
• 20 Amp to 1200 Amp Siemens breakers
• 15 Amp to 1200 Amp Federal Pacific (FPE) breakers
• Single-phase and 3-phase commercial breakers

Whether you need residential breaker replacements, commercial electrical upgrades, or industrial breaker solutions, our knowledgeable staff can help you select the right product for your project.

Serving the Golden Triangle area & Greater San Diego

We proudly provide circuit breakers and electrical supplies throughout:

• Allied Gardens
• Hillcrest
• Golden Hill
• Bankers Hill
• University City
• Vista
• Oceanside
• Carlsbad
• San Marcos
• All San Diego County

We also ship many products nationwide for customers outside the San Diego region.

Your Local Circuit Breaker Experts

At Electrical Supplies Unlimited, we combine decades of electrical supply expertise with one of the region’s most diverse inventories of circuit breakers and electrical equipment.

Whether you’re replacing outdated breakers, sourcing specialty equipment, or upgrading electrical infrastructure, ESU delivers dependable products, expert guidance, and exceptional customer service.

Call ESU today at 858.558.2850 to speak directly with one of our electrical supply specialists and find the right circuit breaker or electrical solution for your needs.

Circuit Breakers Miramar San Diego – New & Used Breakers, Panels & Electrical Supplies

Electrical Supplies Unlimited (ESU) is your trusted source for Circuit Breakers in Miramar San Diego, serving contractors, electricians, property managers, and homeowners throughout Miramar and surrounding communities including University City, Hillcrest, Golden Hill, Bankers Hill, and greater San Diego County.

We buy and sell both new and used circuit breakers, electrical panels, transformers, and electrical equipment. Whether you need replacement breakers, obsolete breakers, or hard-to-find electrical components, ESU provides dependable solutions backed by over 40 years of industry experience.

San Diego’s Trusted Circuit Breaker Supplier Since 1985

ESU has proudly served the San Diego electrical supply industry for more than four decades. As a fully stocked electrical distributor and wholesaler, we carry a wide range of residential, commercial, and industrial electrical supplies designed to meet virtually any project requirement.

Our experienced team specializes in locating discontinued, surplus, and specialty electrical products, helping customers source reliable solutions quickly and efficiently.

Leading Circuit Breaker Brands Available

Our extensive inventory includes major circuit breaker manufacturers and trusted industry brands, including:

General Electric (GE), Siemens / ITE, Cutler Hammer, Square D, Federal Pacific (FPE), Pushmatic, Zinsco, Challenger, Bryant, Westinghouse, Sylvania, Crouse Hinds, Bulldog, and many more.

Complete Electrical Supply Inventory

In addition to circuit breakers, ESU stocks a large inventory of:

• Transformers
• Panelboards up to 600V
• Disconnects & Safety Switches
• Fuses up to 3000 Amps
• Meter Sockets
• Motor Starters & Relays
• Lighting Ballasts & Fixtures
• Bolt Switch Pullouts
• Commercial & Residential Electrical Supplies

We also offer Greenlee tool rentals, conduit benders, wire pullers, and additional electrician equipment for contractors throughout San Diego County.

Specialists in New, Used & Obsolete Circuit Breakers

ESU is San Diego’s go-to source for new, used, surplus, and obsolete circuit breakers. We carry a broad range of amperages and voltages for nearly every major electrical system.

Examples of our inventory include:

• 20 Amp to 125 Amp Zinsco breakers
• 15 Amp to 100 Amp Pushmatic breakers
• 20 Amp to 1200 Amp Siemens breakers
• 15 Amp to 1200 Amp Federal Pacific (FPE) breakers
• Single-phase and 3-phase commercial breakers

Whether you need residential breaker replacements, commercial electrical upgrades, or industrial breaker solutions, our knowledgeable staff can help you select the right product for your project.

Serving Miramar & Greater San Diego

We proudly provide circuit breakers and electrical supplies throughout:

• Allied Gardens
• Hillcrest
• Golden Hill
• Bankers Hill
• University City
• Vista
• Oceanside
• Carlsbad
• San Marcos
• All San Diego County

We also ship many products nationwide for customers outside the San Diego region.

Your Local Circuit Breaker Experts

At Electrical Supplies Unlimited, we combine decades of electrical supply expertise with one of the region’s most diverse inventories of circuit breakers and electrical equipment.

Whether you’re replacing outdated breakers, sourcing specialty equipment, or upgrading electrical infrastructure, ESU delivers dependable products, expert guidance, and exceptional customer service.

Call ESU today at 858.558.2850 to speak directly with one of our electrical supply specialists and find the right circuit breaker or electrical solution for your needs.

Circuit Breakers Bay Ho San Diego – New & Used Breakers, Panels & Electrical Supplies

Electrical Supplies Unlimited (ESU) is your trusted source for Circuit Breakers in Bay Ho San Diego, serving contractors, electricians, property managers, and homeowners throughout Bay Ho and surrounding communities including University City, Hillcrest, Golden Hill, Bankers Hill, and greater San Diego County.

We buy and sell both new and used circuit breakers, electrical panels, transformers, and electrical equipment. Whether you need replacement breakers, obsolete breakers, or hard-to-find electrical components, ESU provides dependable solutions backed by over 40 years of industry experience.

San Diego’s Trusted Circuit Breaker Supplier Since 1985

ESU has proudly served the San Diego electrical supply industry for more than four decades. As a fully stocked electrical distributor and wholesaler, we carry a wide range of residential, commercial, and industrial electrical supplies designed to meet virtually any project requirement.

Our experienced team specializes in locating discontinued, surplus, and specialty electrical products, helping customers source reliable solutions quickly and efficiently.

Leading Circuit Breaker Brands Available

Our extensive inventory includes major circuit breaker manufacturers and trusted industry brands, including:

General Electric (GE), Siemens / ITE, Cutler Hammer, Square D, Federal Pacific (FPE), Pushmatic, Zinsco, Challenger, Bryant, Westinghouse, Sylvania, Crouse Hinds, Bulldog, and many more.

Complete Electrical Supply Inventory

In addition to circuit breakers, ESU stocks a large inventory of:

• Transformers
• Panelboards up to 600V
• Disconnects & Safety Switches
• Fuses up to 3000 Amps
• Meter Sockets
• Motor Starters & Relays
• Lighting Ballasts & Fixtures
• Bolt Switch Pullouts
• Commercial & Residential Electrical Supplies

We also offer Greenlee tool rentals, conduit benders, wire pullers, and additional electrician equipment for contractors throughout San Diego County.

Specialists in New, Used & Obsolete Circuit Breakers

ESU is San Diego’s go-to source for new, used, surplus, and obsolete circuit breakers. We carry a broad range of amperages and voltages for nearly every major electrical system.

Examples of our inventory include:

• 20 Amp to 125 Amp Zinsco breakers
• 15 Amp to 100 Amp Pushmatic breakers
• 20 Amp to 1200 Amp Siemens breakers
• 15 Amp to 1200 Amp Federal Pacific (FPE) breakers
• Single-phase and 3-phase commercial breakers

Whether you need residential breaker replacements, commercial electrical upgrades, or industrial breaker solutions, our knowledgeable staff can help you select the right product for your project.

Serving Bay Ho & Greater San Diego

We proudly provide circuit breakers and electrical supplies throughout:

• Allied Gardens
• Hillcrest
• Golden Hill
• Bankers Hill
• University City
• Vista
• Oceanside
• Carlsbad
• San Marcos
• All San Diego County

We also ship many products nationwide for customers outside the San Diego region.

Your Local Circuit Breaker Experts

At Electrical Supplies Unlimited, we combine decades of electrical supply expertise with one of the region’s most diverse inventories of circuit breakers and electrical equipment.

Whether you’re replacing outdated breakers, sourcing specialty equipment, or upgrading electrical infrastructure, ESU delivers dependable products, expert guidance, and exceptional customer service.

Call ESU today at 858.558.2850 to speak directly with one of our electrical supply specialists and find the right circuit breaker or electrical solution for your needs.

Ground Fault (GFCI) Circuit Breakers: What They Are and How They Work

Ground fault circuit interrupter (GFCI) breakers are designed to protect people from electrical shock by quickly shutting off power when a ground fault is detected. These breakers are essential for maintaining electrical safety in residential, commercial, and outdoor environments.

GFCI protection is required by modern electrical codes in areas where water and electricity may come into contact, making them one of the most important safety components in any electrical system.

What Is a GFCI Circuit Breaker?

A GFCI circuit breaker monitors the flow of electricity in a circuit. If it detects an imbalance between the outgoing and returning current, it immediately shuts off power to prevent electrical shock.

This reaction happens in milliseconds, significantly reducing the risk of serious injury or electrocution.

How GFCI Breakers Work

Under normal conditions, electrical current flows evenly through the circuit. When a ground fault occurs—such as electricity flowing through water or a person—the GFCI breaker detects the imbalance and trips instantly.

This rapid response is what makes GFCI breakers a critical safety feature in modern electrical systems.

Where GFCI Breakers Are Required

GFCI protection is required in areas where moisture is present or where electrical shock risk is higher. Common locations include:

• Kitchens
• Bathrooms
• Garages
• Outdoor outlets
• Basements and crawl spaces
• Laundry rooms

Local electrical codes may vary, but most modern installations require GFCI protection in these areas.

GFCI Breaker vs GFCI Outlet

GFCI protection can be provided either by a breaker or an outlet. Understanding the difference is important:

• GFCI Breaker: Protects the entire circuit from the electrical panel
• GFCI Outlet: Protects a single outlet or downstream outlets

GFCI breakers are often preferred when multiple outlets need protection or when upgrading older electrical systems.

Common Reasons GFCI Breakers Trip

GFCI breakers are designed to trip when a fault is detected, but frequent tripping may indicate an issue. Common causes include:

• Moisture exposure
• Faulty appliances
• Damaged wiring
• Ground faults in the circuit

If your breaker trips often, read our guide on why circuit breakers keep tripping.

When to Upgrade to GFCI Protection

If your electrical system does not include GFCI protection in required areas, upgrading is strongly recommended. This is especially important in older homes where safety standards may not meet current code requirements.

Learn more about upgrading your system in our guide on when to upgrade your electrical panel.

Choosing the Right GFCI Circuit Breaker

Selecting the correct GFCI breaker depends on your panel type, circuit requirements, and electrical load. Compatibility with your panel brand is critical to ensure safe and proper operation.

For help selecting the right breaker, visit our How to Choose the Right Circuit Breaker guide.

GFCI Breakers and Electrical Safety

Installing GFCI breakers significantly improves electrical safety by reducing the risk of shock and preventing dangerous electrical conditions. They are one of the most effective safety upgrades for residential and commercial systems.

Explore More Circuit Breaker Resources

To learn more about circuit breaker types, safety, and troubleshooting, visit our Circuit Breaker Resource Hub.

• Tandem Circuit Breakers
• How Many Breakers Can Be in a Panel
• Circuit Breaker Panel Upgrade Cost