Circuit Breakers in Sunbow, San Diego. ESU buys and sells new & used Breakers and Panels!

Electrical Supplies Unlimited buys and sells new & used Circuit Breakers in Sunbow  San Diego surrounding areas including Chula Vista, 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 Sunbow, 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!

Tandem Circuit Breakers: What They Are and When to Use Them

A tandem circuit breaker is a special type of breaker that allows two separate circuits to be installed in a single slot within an electrical panel. These breakers are often used when a panel runs out of space but additional circuits are needed.

Understanding how tandem breakers work, when they are allowed, and whether they are safe is essential for homeowners, electricians, and contractors working with residential electrical systems.

What Is a Tandem Circuit Breaker?

A tandem circuit breaker (sometimes called a “double” or “cheater” breaker) combines two individual breakers into one unit that fits into a single panel slot. Each circuit operates independently, providing the same protection as a standard single-pole breaker.

This allows an electrical panel to support more circuits without physically expanding the panel.

When Are Tandem Breakers Used?

Tandem breakers are typically used when an electrical panel has no available space for additional circuits. Common situations include:

• Home renovations or additions
• Installing new appliances or equipment
• Adding circuits for kitchens, garages, or HVAC systems
• Upgrading electrical capacity without replacing the panel

They provide a convenient solution when space is limited, but they are not always the best long-term option.

Are Tandem Circuit Breakers Safe?

Yes, tandem circuit breakers are safe when used correctly and installed in panels that are specifically designed to accept them. Electrical panels have a maximum number of circuits they can safely handle, and tandem breakers should only be used within those limits.

Installing tandem breakers in a panel that is not rated for them can lead to overheating, code violations, and potential electrical hazards.

Are Tandem Breakers Legal?

Tandem breakers are legal when used in accordance with the panel manufacturer’s specifications and local electrical codes. Most panels include labeling that indicates how many tandem breakers are allowed and in which positions they can be installed.

If too many circuits are added beyond the panel’s rating, it may be necessary to upgrade the panel instead.

Tandem Breaker vs Standard Breaker

Understanding the difference between tandem and standard breakers is important when planning electrical upgrades:

• Standard Breaker: Occupies one slot and controls one circuit
• Tandem Breaker: Occupies one slot but controls two separate circuits

While tandem breakers increase circuit capacity, they do not increase the total electrical load capacity of the panel.

Tandem Breakers vs Double-Pole Breakers

Tandem breakers are sometimes confused with double-pole breakers, but they serve different purposes:

• Tandem Breaker: Two independent 120V circuits
• Double-Pole Breaker: One 240V circuit for large appliances

Using the correct type of breaker is critical for proper electrical system function.

When You Should Upgrade Your Electrical Panel

If you find yourself needing multiple tandem breakers to add circuits, it may be a sign that your panel is undersized for your electrical needs. In these cases, upgrading to a larger panel may be the safer and more reliable solution.

Learn more about upgrade costs in our guide to circuit breaker panel upgrade cost.

Choosing the Right Circuit Breaker

Selecting the correct breaker for your panel ensures safe and reliable operation. Breakers must be compatible with your panel brand and rated for the correct electrical load.

For more guidance, visit our How to Choose the Right Circuit Breaker guide.

Explore More Circuit Breaker Resources

For additional information on breaker types, troubleshooting, and electrical safety, visit our Circuit Breaker Resource Hub.

Circuit Breaker Replacement Guide

Knowing when and how to perform a circuit breaker replacement is important for maintaining a safe and reliable electrical system. Whether you are replacing a faulty breaker, upgrading an older electrical panel, or installing new equipment, choosing the correct replacement breaker helps protect wiring, appliances, and electrical devices from overloads and short circuits.

This guide explains common signs of breaker failure, how to identify the correct replacement, and important factors to consider before installing a new circuit breaker.

When Should a Circuit Breaker Be Replaced?

Circuit breakers are designed to last for many years, but they can eventually wear out or become damaged. A breaker that no longer functions properly may fail to trip during an overload, creating a serious safety hazard.

Common signs that indicate a breaker may need replacement include frequent tripping, burning odors near the panel, visible damage, overheating, or a breaker that will not reset.

If you are experiencing these issues, read our guide on Signs of a Bad Circuit Breaker.

Step 1: Identify the Cause of the Problem

Before replacing a breaker, it is important to determine whether the breaker itself is defective or if another electrical issue is causing the problem.

Overloaded circuits, short circuits, damaged wiring, and faulty appliances can all cause breakers to trip. Simply replacing the breaker without correcting the underlying issue may not solve the problem.

Step 2: Verify Panel Compatibility

Not all circuit breakers are interchangeable. Replacement breakers must be compatible with the specific electrical panel in which they are installed.

Major panel and breaker manufacturers include Siemens, Square D, Eaton, Cutler Hammer, General Electric (GE), Federal Pacific (FPE), Challenger, Pushmatic, and Zinsco. Always verify compatibility before purchasing a replacement breaker.

For additional guidance, visit our How to Choose the Right Circuit Breaker resource.

Step 3: Match the Correct Amperage Rating

Replacement breakers must have the proper amperage rating for the circuit they protect. Installing an oversized breaker can allow wiring to overheat, while an undersized breaker may trip unnecessarily.

Common residential breaker sizes include:

• 15 Amp circuit breakers
• 20 Amp circuit breakers
• 30 Amp circuit breakers
• 40 Amp circuit breakers
• 50 Amp circuit breakers

The replacement breaker should match both the circuit requirements and conductor size.

Common Circuit Breaker Replacement Situations

Many property owners replace circuit breakers for one of the following reasons:

• Breaker repeatedly trips under normal load
• Breaker will not reset
• Panel upgrade or renovation project
• Replacing obsolete breakers
• Replacing recalled or unsafe electrical equipment

Older Federal Pacific (FPE), Challenger, and Zinsco breakers are commonly replaced during electrical upgrades due to safety concerns and limited availability.

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

Should You Upgrade the Entire Electrical Panel?

In some situations, replacing a single breaker may not be enough. Older panels that are overloaded or lack capacity for modern electrical demands may benefit from a complete panel upgrade.

If your panel is full, you may also be considering options such as Tandem Circuit Breakers or adding additional circuits.

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

Cost of Circuit Breaker Replacement

The cost of replacing a circuit breaker depends on several factors, including breaker type, amperage, panel manufacturer, and labor requirements. Specialty and obsolete breakers may cost more than standard residential breakers.

If a larger electrical upgrade is needed, review our resource on Circuit Breaker Panel Upgrade Cost.

Finding Replacement Circuit Breakers in San Diego

Electrical Supplies Unlimited carries a large inventory of new, used, surplus, and obsolete circuit breakers for residential, commercial, and industrial applications. We stock breakers from many leading manufacturers and can help locate hard-to-find replacement breakers for older electrical systems.

Whether you need a standard residential breaker or a specialty industrial breaker, our experienced staff can help identify the correct replacement.

More Circuit Breaker Resources

• Circuit Breaker Resource Hub
• How to Choose the Right Circuit Breaker
• Signs of a Bad Circuit Breaker
• When to Upgrade Your Electrical Panel
• Circuit Breaker Store San Diego

Hard to Find Circuit Breakers in San Diego

Need a discontinued, obsolete, or hard-to-find circuit breaker? Electrical Supplies Unlimited (ESU) specializes in locating and supplying hard to find circuit breakers in San Diego for residential, commercial, and industrial electrical systems. With over 40 years of experience and an extensive inventory of new, used, surplus, and obsolete electrical equipment, we help electricians, contractors, facility managers, and property owners find replacement breakers that many suppliers can no longer source.

Whether you need a replacement breaker for an older panel, a discontinued manufacturer, or a specialized industrial application, ESU is one of San Diego's trusted sources for difficult-to-find electrical components.

Why Are Some Circuit Breakers Difficult to Find?

Many electrical panels remain in service for decades after manufacturers discontinue production. As equipment ages, replacement breakers become increasingly difficult to locate through traditional electrical distributors.

Common reasons circuit breakers become hard to find include:

• Manufacturer discontinuation
• Panel systems no longer in production
• Limited inventory availability
• Specialized commercial or industrial applications
• Obsolete electrical equipment
• Older residential electrical panels

Fortunately, ESU maintains inventory and supplier relationships that allow us to locate many discontinued and hard-to-find breaker models.

Popular Hard-to-Find Circuit Breaker Brands

We frequently help customers locate replacement breakers for older and discontinued systems, including:

• Federal Pacific (FPE)
• Zinsco
• Challenger
• Pushmatic
• Bulldog
• Bryant
• Westinghouse
• Sylvania
• ITE Siemens Legacy Models
• Crouse-Hinds
• General Electric (GE)
• Square D Obsolete Models

Our inventory changes regularly, so if you cannot locate a breaker elsewhere, contact our team for assistance.

Replacement Breakers for Obsolete Electrical Panels

Many older homes and commercial buildings throughout San Diego still contain electrical panels that require obsolete circuit breakers. Rather than replacing an entire electrical panel, many property owners choose to source compatible replacement breakers when repairs or maintenance are required.

Learn more in our guide on Obsolete Circuit Breakers.

Hard to Find Commercial and Industrial Circuit Breakers

Commercial and industrial facilities often utilize specialty circuit breakers that are not commonly stocked by local suppliers. ESU can assist with locating:

• 3-Phase Circuit Breakers
• 480 Volt Circuit Breakers
• Molded Case Circuit Breakers
• Bolt-On Circuit Breakers
• Panelboard Breakers
• Industrial Distribution Equipment
• Medium Voltage Breakers

We understand the urgency of keeping electrical systems operational and work to locate replacement equipment as quickly as possible.

Common Signs You Need a Replacement Breaker

If you are searching for a replacement breaker, you may already be experiencing signs of breaker failure.

• Breaker repeatedly trips
• Breaker will not reset
• Visible damage or overheating
• Burn marks near the breaker
• Intermittent power loss
• Electrical panel issues

Learn more in our resources:

• Signs of a Bad Circuit Breaker
• Circuit Breaker Not Resetting
• Circuit Breaker Replacement Guide

Why Contractors Choose ESU

Electrical contractors throughout San Diego rely on ESU because we offer:

• Over 40 years of electrical industry experience
• Large inventory of new and used breakers
• Obsolete and discontinued breaker sourcing
• Residential, commercial, and industrial products
• Knowledgeable electrical supply specialists
• Fast turnaround on difficult-to-find items

Our team understands electrical equipment and can often help identify compatible replacements even when model numbers are difficult to read or no longer available.

Hard to Find Circuit Breakers in San Diego

Electrical Supplies Unlimited proudly serves electricians, contractors, property managers, facilities maintenance teams, and homeowners throughout San Diego County. We maintain one of the area's most diverse inventories of circuit breakers and electrical equipment.

If you're searching for a hard-to-find breaker, obsolete breaker, discontinued breaker, or replacement electrical component, contact ESU today. Chances are we either have it in stock or can help locate it.

More Circuit Breaker Resources

• Circuit Breaker Resource Hub
• Circuit Breakers San Diego
• Buy Circuit Breakers San Diego
• Obsolete Circuit Breakers
• Replacing FPE, Zinsco, and Challenger Breakers
• Circuit Breaker Store San Diego