Circuit Breakers University Heights San Diego
Circuit Breakers Miramar San Diego

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

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.

Thermal Magnetic Circuit Breakers

Thermal magnetic circuit breakers are one of the most widely used types of circuit protection in residential, commercial, and industrial electrical systems. They combine two separate protection mechanisms—thermal protection for overloads and magnetic protection for short circuits—making them highly reliable and efficient.

These breakers are commonly found in modern electrical panels and are essential for protecting wiring, appliances, and electrical systems from damage caused by excessive current.

How Thermal Magnetic Circuit Breakers Work

Thermal magnetic circuit breakers use a dual protection system:

  • Thermal element: Responds to sustained overloads by heating a bimetal strip that trips the breaker.
  • Magnetic element: Responds instantly to short circuits using electromagnetic force to trip the breaker.

This combination allows the breaker to protect against both slow-building overloads and sudden electrical faults.

Where Thermal Magnetic Breakers Are Used

These breakers are standard in many electrical applications, including:

  • Residential electrical panels
  • Commercial buildings
  • Industrial equipment
  • HVAC systems
  • Motor control circuits

In San Diego, they are commonly used in both new construction and panel upgrades to meet modern electrical code requirements.

Benefits of Thermal Magnetic Circuit Breakers

  • Dual protection against overloads and short circuits
  • Reliable and long-lasting performance
  • Widely available and cost-effective
  • Compatible with most modern electrical panels

Thermal Magnetic vs Other Circuit Breakers

Unlike specialty breakers such as AFCI or GFCI breakers, thermal magnetic breakers focus on core electrical protection. They do not provide arc-fault or ground-fault protection but are essential as the primary layer of circuit safety.

Learn more about other breaker types in our guide on circuit breaker types and applications.

When to Replace a Thermal Magnetic Circuit Breaker

You may need to replace a breaker if you notice:

  • Frequent tripping under normal load
  • Physical damage or burn marks
  • Breaker fails to reset properly
  • Outdated or incompatible panel systems

If your breaker is frequently tripping, visit our guide on why circuit breakers keep tripping.

Used in San Diego Electrical Systems

Thermal magnetic circuit breakers are commonly used throughout San Diego homes and businesses due to their reliability and compliance with electrical code standards.

They are often installed during:

  • Panel upgrades
  • New construction projects
  • Electrical system repairs
  • Equipment replacements

For local electrical solutions, visit our main page on circuit breakers in San Diego.

Related Circuit Breaker Resources

Circuit Breaker Resources & Guides!

Welcome to ESU’s Circuit Breaker Resources Hub — your ultimate guide to understanding, selecting, and maintaining circuit breakers for residential, commercial, and industrial applications. Whether you’re an electrician, contractor, or a homeowner looking to upgrade your electrical panel, this hub provides authoritative guides, brand comparisons, safety tips, and troubleshooting advice to help you make informed decisions.

 

Why Understanding Circuit Breakers Matters

Circuit breakers are the heart of any electrical system. They protect your home, business, or industrial facility from electrical overloads and short circuits, preventing fires and costly equipment damage. Selecting the right circuit breaker is essential for safety, compliance, and long-term reliability.

Our resources cover all aspects of circuit breakers, from low voltage residential breakers to medium voltage industrial solutions, and help you navigate the many brands, types, and technical specifications available.

Explore Our Guides & Resources

Below, you’ll find our full library of guides — each page is designed to provide in-depth knowledge, actionable tips, and expert advice:

Circuit Breaker Buying Guide

Everything you need to know to buy the right circuit breaker for your project, from residential panels to industrial systems.

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!

 

Discontinued Circuit Breakers: Finding Replacement Breakers for Older Electrical Systems

Many homes, commercial buildings, and industrial facilities continue to operate with electrical panels that require discontinued circuit breakers. When a breaker fails or additional circuits are needed, locating a compatible replacement can be challenging. Electrical Supplies Unlimited (ESU) specializes in helping customers find replacement breakers for obsolete and discontinued electrical systems throughout San Diego and Southern California.

Whether you're an electrician, contractor, facility manager, or property owner, understanding your options for discontinued breakers can help extend the life of your electrical system and avoid unnecessary panel replacement costs.

 alt=What Are Discontinued Circuit Breakers?

Discontinued circuit breakers are breakers that are no longer manufactured by the original company. Although production has ended, many of these breakers remain in service in residential, commercial, and industrial electrical panels throughout the United States.

As electrical equipment ages, replacement breakers often become difficult to locate through traditional electrical supply channels. This creates a growing demand for surplus, obsolete, and hard-to-find replacement breakers.

Common Discontinued Circuit Breaker Brands

Some of the most frequently requested discontinued breaker brands include:

  • Federal Pacific (FPE)
  • Zinsco
  • Challenger
  • Pushmatic
  • Bulldog
  • Bryant
  • Westinghouse
  • Sylvania
  • Crouse-Hinds
  • ITE Legacy Models

Many of these systems were installed decades ago and continue operating today, making replacement breakers an ongoing necessity.

Why Are Circuit Breakers Discontinued?

Manufacturers discontinue breaker lines for several reasons:

  • Product redesigns and technology upgrades
  • Company mergers and acquisitions
  • Changes in electrical code requirements
  • Reduced market demand
  • Introduction of newer breaker platforms

Even when production ends, many panels remain functional and continue requiring replacement components for maintenance and repairs.

Can You Still Buy Discontinued Circuit Breakers?

In many cases, yes. Discontinued breakers are often available through specialized suppliers that deal in surplus, obsolete, and hard-to-find electrical equipment.

Replacement options may include:

  • New surplus breakers
  • Professionally tested used breakers
  • Reconditioned breakers
  • Manufacturer-approved replacement solutions

Working with an experienced electrical supplier can help ensure compatibility and safe operation.

Federal Pacific, Zinsco, and Challenger Breakers

Among the most searched discontinued breaker brands are Federal Pacific (FPE), Zinsco, and Challenger. These panels remain common in older residential and commercial buildings throughout California.

Learn more in our guide on Replacing FPE, Zinsco, and Challenger Breakers.

How to Identify a Discontinued Circuit Breaker

Before purchasing a replacement breaker, it's important to identify:

  • Manufacturer
  • Breaker model number
  • Amperage rating
  • Voltage rating
  • Panel compatibility

If labels are missing or difficult to read, an experienced electrical supplier may be able to identify the breaker based on physical appearance and panel information.

Visit our Circuit Breaker Identification Guide for additional help.

When Should You Replace the Entire Panel?

Although replacement breakers are often available, some electrical systems may benefit from a complete panel upgrade.

Factors that may indicate a panel replacement is appropriate include:

  • Frequent breaker failures
  • Limited panel capacity
  • Physical damage or corrosion
  • Major electrical renovations
  • Increasing power requirements

Learn more in our guide on When to Upgrade Your Electrical Panel.

Discontinued Circuit Breakers in San Diego

Electrical Supplies Unlimited maintains inventory of many discontinued, obsolete, and hard-to-find circuit breakers for customers throughout San Diego County. Our team works with electricians, contractors, maintenance departments, and property managers to help locate replacement breakers quickly and efficiently.

Whether you need a discontinued residential breaker, a commercial panel component, or a hard-to-find industrial breaker, ESU can help identify and source the right solution.

Why Choose ESU?

For more than 40 years, Electrical Supplies Unlimited has been one of San Diego's trusted sources for circuit breakers, transformers, electrical panels, and obsolete electrical equipment.

  • Large inventory of discontinued breakers
  • New, used, and surplus inventory available
  • Experienced electrical supply specialists
  • Residential, commercial, and industrial expertise
  • Hard-to-find electrical equipment sourcing
  • Serving all of San Diego County

We specialize in helping customers find replacement breakers that many traditional suppliers can no longer obtain.

More Circuit Breaker Resources