Sub panel breaker boxes serve as supplementary electrical distribution points within your home, branching off from the main electrical panel. Understanding how they work and their importance will empower you to make informed decisions about your electrical system.
Throughout this guide, we will discuss the different types of sub panel breaker boxes, their installation process, and their usage. By the end, you’ll have a firm grasp on everything you need to know about these essential components.
So, whether you’re a DIY enthusiast or a professional electrician, join us as we demystify sub panel breaker boxes and equip you with the knowledge to navigate the world of electrical systems confidently. Let’s get started!
A sub panel breaker box, also known as a subpanel or a distribution panel, is an additional electrical panel that is connected to the main electrical panel in your home. It serves as a localized distribution point for electricity, allowing you to power specific areas or circuits within your house.
Unlike the main electrical panel, which receives electricity directly from the utility company, a sub panel breaker box gets its power from the main panel. It acts as a hub, distributing electricity to various circuits in a designated area of your home. This enables you to have greater control over the electrical supply in different parts of your house.
Sub panel breaker boxes are typically installed in areas where there is a high demand for electrical power, such as kitchens, workshops, or home offices. They can also be used to accommodate additional circuits when the main panel is already at its capacity.
The sub panel breaker box consists of a metal enclosure, circuit breakers, bus bars, and neutral and ground bars. The circuit breakers protect the circuits from overloading and tripping, ensuring the safety of your electrical system.
You might be wondering why you need a sub panel breaker box when you already have a main electrical panel. The answer lies in the benefits and practicality it offers.
1. Increased capacity: The main electrical panel has a limited number of slots for circuit breakers. When you run out of slots, adding more circuits becomes challenging. A sub panel breaker box provides additional slots, allowing you to expand your electrical system without overloading the main panel.
2. Convenience: By having localized sub panel breaker boxes, you can easily control and manage the power supply to specific areas of your home. This is especially useful if you have separate areas that require different electrical needs, such as a garage, workshop, or an outdoor entertainment area.
3. Reduced wiring complexity: Instead of running lengthy electrical wires from the main panel to distant areas of your home, a sub panel breaker box allows you to have a shorter, more efficient wiring setup. This not only saves on wiring costs but also reduces the risk of voltage drop and electrical interference.
4. Improved safety: Sub panel breaker boxes come with their own set of circuit breakers, providing an additional layer of protection for your electrical circuits. In the event of an overload or short circuit, the circuit breakers in the sub panel will trip, isolating the problem and preventing damage to the main panel.
Overall, a sub panel breaker box offers flexibility, convenience, and enhanced safety, making it an essential component for any homeowner or electrical professional.
Sub panel breaker boxes come in a variety of types, each designed to meet specific electrical needs. Here are the most common types:
1. Main Lug Only (MLO) Sub Panel: This type of sub panel breaker box does not have a main circuit breaker. Instead, it relies on the main panel’s circuit breaker for protection. MLO sub panels are typically used as secondary panels and are connected directly to the main panel.
2. Main Breaker Sub Panel: Unlike MLO sub panels, main breaker sub panels have their own main circuit breaker. This provides an additional level of protection, allowing you to disconnect power to the entire sub panel if needed. Main breaker sub panels are commonly used in residential applications.
3. Transfer Switch Sub Panel: Transfer switch sub panels are used in homes with backup generators. They allow you to switch between the utility power and generator power seamlessly during power outages. The transfer switch sub panel automatically detects the loss of utility power and transfers the load to the generator.
4. Specialty Sub Panels: There are also specialty sub panels designed for specific purposes, such as spa sub panels, pool sub panels, or sub panels for detached buildings. These sub panels have unique features and safety requirements tailored to their intended use.
When choosing a sub panel breaker box, consider factors such as the electrical load requirements, available space, and the specific needs of your electrical system. Consulting with a licensed electrician is recommended to ensure you select the right sub panel for your home.
To understand how a sub panel breaker box works, let’s take a closer look at its components and the flow of electricity within the system.
1. Power supply: The sub panel breaker box receives electricity from the main electrical panel through a dedicated feeder cable. This cable is typically sized according to the electrical load requirements of the sub panel.
2. Main circuit breaker: In a main breaker sub panel, the main circuit breaker acts as the primary disconnect switch, allowing you to turn off power to the entire sub panel. This is useful for maintenance or in the event of an emergency.
3. Bus bars: The sub panel breaker box has two bus bars – the neutral bus bar and the ground bus bar. The neutral bus bar is connected to the neutral wire, which carries the current back to the utility transformer. The ground bus bar is connected to the grounding system, providing a safe path for electrical faults.
4. Circuit breakers: The circuit breakers in the sub panel protect individual circuits from overloading or short circuits. Each circuit breaker corresponds to a specific circuit and can be turned on or off independently. When a circuit experiences an overload or short circuit, the corresponding circuit breaker will trip, cutting off power to that circuit.
5. Branch circuits: The sub panel breaker box distributes electricity to various branch circuits, which are connected to the circuit breakers. Each branch circuit supplies power to specific outlets, lighting fixtures, or appliances in a designated area of your home.
It’s important to ensure that the electrical load of the sub panel does not exceed its capacity. Overloading the sub panel can lead to overheating, circuit breaker trips, and potential damage to your electrical system. Consulting with a licensed electrician is crucial for proper installation and load calculation.
Installing a sub panel breaker box requires electrical knowledge and expertise. While this guide provides a general overview of the installation process, it is important to consult with a licensed electrician for your specific installation. Here are the general steps involved:
1. Determine the location: Choose a suitable location for the sub panel breaker box. It should be easily accessible, well-ventilated, and away from flammable materials. Check local building codes for any specific requirements.
2. Shut off power: Before starting any electrical work, shut off power to the main electrical panel. This can be done by turning off the main circuit breaker or removing the main panel’s service disconnect.
3. Mount the sub panel: Install the sub panel breaker box on the chosen location, ensuring it is securely fastened. Follow the manufacturer’s instructions for proper mounting.
4. Connect the feeder cable: Run the feeder cable from the main panel to the sub panel breaker box. The cable should be sized according to the electrical load requirements and local codes. Connect the feeder cable to the main panel and the sub panel, making sure to tighten the connections properly.
5. Connect the neutral and ground wires: Connect the neutral wire from the feeder cable to the neutral bus bar in the sub panel. Connect the ground wire from the feeder cable and any additional grounding wires to the ground bus bar. Ensure all connections are secure.
6. Install circuit breakers: Install the circuit breakers in the sub panel breaker box, making sure to match the electrical load requirements of each circuit. Connect the branch circuits to the respective circuit breakers, following proper wiring practices.
7. Label and test: Label each circuit in the sub panel breaker box for easy identification. Once all connections are made, restore power to the main panel and test each circuit to ensure they are functioning correctly.
Remember, electrical work can be dangerous and should only be performed by qualified individuals. If you are unsure about any aspect of the installation process, consult with a licensed electrician for guidance and assistance.
While sub panel breaker boxes are designed to operate smoothly, occasional issues may arise. Here are some common problems and troubleshooting tips to help you resolve them:
1. Tripped circuit breakers: If a circuit breaker trips, it means that there is an overload or a short circuit in the circuit. Start by identifying the circuit that is affected and unplug or disconnect any devices connected to it. Reset the tripped circuit breaker by switching it off and then on again. If the circuit breaker continues to trip, consult with a licensed electrician.
2. Flickering lights or intermittent power: Flickering lights or intermittent power can be caused by loose connections, faulty wiring, or overloaded circuits. Check all connections in the sub panel breaker box to ensure they are tight and secure. If the issue persists, consult with a licensed electrician to identify and resolve the underlying cause.
3. Hot or buzzing breaker box: A hot or buzzing breaker box can indicate an electrical problem, such as loose connections or overloaded circuits. Turn off power to the sub panel breaker box immediately and contact a licensed electrician to inspect and repair the issue. Do not attempt to fix the problem yourself, as it can be dangerous.
4. Inadequate capacity: If you find that your sub panel breaker box is consistently tripping circuit breakers or unable to handle the electrical load, it may be an indication that you need to upgrade to a larger sub panel or reevaluate your electrical needs. Consult with a licensed electrician to assess your electrical system and recommend the appropriate solution.
Remember, safety should always be a top priority when dealing with electrical systems. If you are unsure about how to troubleshoot or resolve any issues with your sub panel breaker box, seek professional assistance.
Upgrading your electrical system with a sub panel breaker box can provide numerous benefits, such as increased capacity, improved organization, and enhanced safety. Here are some considerations to keep in mind when planning an upgrade:
1. Evaluate your electrical needs: Assess your current and future electrical needs to determine the appropriate size and capacity of the sub panel breaker box. Consider factors such as the number of circuits, types of appliances or equipment, and any planned expansions or renovations.
2. Consult with a licensed electrician: Consulting with a licensed electrician is crucial for a thorough assessment of your electrical system and to ensure compliance with local codes and regulations. They can help determine the ideal location for the sub panel breaker box and provide expert guidance on the installation process.
3. Plan for future growth: When upgrading your electrical system, it’s important to consider future growth and potential electrical demands. Installing a sub panel breaker box with more slots than you currently need allows for future expansion without the need for additional upgrades.
4. Label circuits and organize: Proper labeling of circuits in the sub panel breaker box is essential for easy identification and maintenance. Take the time to label each circuit accurately and consider implementing an organizational system, such as color-coding or grouping circuits by area or function.
5. Follow safety guidelines: Ensure that the installation and upgrade of the sub panel breaker box comply with safety guidelines and local electrical codes. This includes using the correct wire sizes, properly grounding the system, and following manufacturer’s instructions for installation and maintenance.
By upgrading your electrical system with a sub panel breaker box, you can effectively manage your electrical load, reduce the risk of overloading circuits, and have greater control over the power distribution within your home.
Safety should always be a priority when working with sub panel breaker boxes and electrical systems. Here are some essential safety considerations:
1. Turn off power: Before working on a sub panel breaker box, always turn off power at the main panel. Use a non-contact voltage tester to ensure that there is no electrical current present.
2. Use appropriate protective gear: Wear appropriate protective gear, such as insulated gloves, safety glasses, and non-conductive footwear, when working on electrical systems. This helps protect you from potential electrical shocks or injuries.
3. Consult a licensed electrician: If you are unsure about any aspect of the installation, maintenance, or troubleshooting process, consult with a licensed electrician. They have the expertise and knowledge to handle electrical systems safely and efficiently.
4. Proper grounding: Ensure that the sub panel breaker box is properly grounded to prevent electrical faults and potential electrical shock hazards. Follow local electrical codes and regulations for grounding requirements.
5. Regular maintenance: Regularly inspect and maintain the sub panel breaker box to ensure it is in good working condition. Check for any signs of damage, loose connections, or overheating. If you notice any issues, contact a licensed electrician for assistance.
Remember, electricity can be dangerous, and improper handling or installation of sub panel breaker boxes can lead to electrical shocks, fires, or other hazards. If you are not confident in your abilities or have limited knowledge of electrical systems, it is recommended to seek professional help.
There are several types of sub panel breaker boxes available in the market, each designed for specific purposes. Understanding the different types can help you determine which one is best suited for your needs.
1. Main Lug Sub Panel Breaker Box
Main lug sub panel breaker boxes are commonly used when you need to add additional circuits to your existing electrical system. These panels do not have a main breaker and are powered directly from the main electrical panel. They are ideal for situations where you want to expand your electrical capacity without adding a main breaker.
Main lug sub panel breaker boxes are typically installed near the main electrical panel and are connected to it using separate feeder wires. They are equipped with multiple slots for circuit breakers, allowing you to add more circuits as needed.
2. Main Breaker Sub Panel Breaker Box
Main breaker sub panel breaker boxes are similar to main lug panels but come with a main breaker. This means that the entire sub panel can be shut off from the main electrical panel using the main breaker. These panels are commonly used when you need to isolate a section of your electrical system for maintenance or repairs.
Main breaker sub panel breaker boxes are typically installed in areas where multiple circuits need to be controlled by a single breaker. They are commonly used in garages, workshops, or outbuildings where a separate electrical system is required.
3. Transfer Switch Sub Panel Breaker Box
Transfer switch sub panel breaker boxes are specialized panels used in standby generator installations. These panels allow you to safely switch between your main electrical supply and the generator during power outages. They are equipped with a transfer switch that ensures a seamless transition between the two power sources.
Transfer switch sub panel breaker boxes are typically installed near the main electrical panel and are connected to the generator using a separate transfer switch. They are essential for homeowners who rely on standby generators for uninterrupted power supply during emergencies.