How to Hook Up a Generator to a Breaker Box

Last Updated on December 27, 2021 by Jahangir

It is very important to hook up a generator to a breaker box properly. Otherwise, your generator will not be able to supply electricity. It’s a question that How to Hook Up a Generator to a Breaker Box? A breaker box is a device that receives the power from the power company/generator and allows to supply the current needed for individual household appliances.

The breaker box is a device that manages the power to a house, and a generator provides power to the household’s electrical devices through the breaker box. It is possible to connect a generator to a breaker box in several ways, but the most basic method is to simply plug it in. It is important to consider several things when you do this. To hook up a generator to a breaker box, you need the following components.

Sl NoName of EquipmentDescriptions
 Electric ToolsWire & Cable Crimpers, cutters, Drilling machine, Multimeter, tape measurement, hammer, screwdrivers, Wrench Set,  Tongue-and-Groove Pliers.
1Safety GearGloves, boots, eye protection and a face mask
2Electric WiresThe size of the electric wires depends on the electric load of the home.
3An Interlock Kit 
4A Breaker 
5An Inlet Plug 
How to Hook Up a Generator to a Breaker Box

Safety Gear

When hooking up a generator to a breaker, safety gear is essential. In order to accomplish anything at all, you need to be prepared first. Whether you plan on working in electricians or other electrically related fields, you should wear a protective helmet, goggles, sturdy shoes, and gloves. In addition, it is also important to have an electric toolset, so you can take advantage of these tools.

It is crucial to have the safety equipment when your generator is hooked up to the breaker box. To start, you need to ensure that you have and wear the safety gear listed, which includes gloves, boots, eye protection, a face mask, and a sturdy workbench or table Sturdy tools. First, you must make sure that you have all the safety gear listed above.

You should also make sure that you are working on a stable surface. Make your workbench or table sturdy. The surface you are working on must be level, flat and level. The next thing you need to do is to make sure that you are wearing protective clothing. Nevertheless, it is vital that you also wear the required safety gear when operating the generator itself. Although many people consider it a safer power tool than other power tools, it can still prove fatal to some – if it is not used correctly.

Electric Wires

Homes and businesses receive electricity from generators via electric wires. They are insulated by rubber or plastic coating to prevent short circuits, and the insulation is covered with a thin layer of aluminium or copper. In order to avoid getting confused, a beginner needs three different colours of wire. There should be one red, one black and one green. Red is best for positive (+) connections to the generator.

Black is for negative (-) connections, i.e. earthing, while green is for grounding. The size of the cable will depend on the load of your home that you want to run on the generator. When choosing the size of the cable, it is important to know the wattage of your generator. The cable will carry that load safely to your home. Below I have attached the chart where you can find the cable size corresponding to the current capacity.

Sl NoCable size in Sq. mmCurrent Carrying CapacityBreaker Size
11.514Amp10Amp
22.522Amp20Amp
3433Amp32Amp
4642Amp40Amp
51058Amp50Amp
61677Amp65Amp
725102Amp80Amp
835125Amp100Amp
950150Amp125Amp
1070192Amp160Amp

If you want to run 102-ampere load on the generator, you need to use 25mm2 wire to supply the current to the load. You can check out our article about how to calculate the total load in a home.

What size generator do I need for my house?

In the event of a power outage, a generator is vital to provide power for a home or a business. In times when your home’s main electrical service is unavailable or not working properly, a standby generator provides continuous, reliable backup electricity. Additionally, it protects your electric system from under voltages and other problems.

An Interlock Kit

An interlock kit is an important part of a home security system. In this case, we will use the generator breaker box. You have to match your generator’s model and specifications with the interlock kit. There are several advantages to using an interlock kit over a transfer switch, including the following:

+ Interlock kits are easy to install, and the entire procedure takes less than a half-hour.

+ Most interlock kits only have a few components and are easy to use

+ Interlock kits are cheaper than transfer switches

+ Interlock kits draw less current than transfer switches

+ Interlock kits are easier to install than transfer switches

+ Interlock kits require less maintenance than transfer switches

Figure 1: An Interlock Kit

Find the breaker box

Generators are a great option for homeowners who want to feel more secure about their power. Generators come in many sizes and can be hooked up to a breaker box. Home circuit breakers are the best way to hook up a generator to your breaker box. To connect the generator with the breaker box, you need to select the right breaker box.

It may not be necessary to install a new breaker if your existing breaker box has several empty spaces, however, most installations will require a new breaker.

You should choose a breaker that matches the generator’s capacity and the electricity load of your home. If your home has a circuit breaker, make sure the circuit breaker is compatible with the generator.

Figure 2:A breaker box with an empty slot

Determine Your Generator Plug Type

In this step, we need to determine the type of generator plug which is very important to connect to the generator. Then you need to confirm whether the generator plug matches the socket of your generator. In the following section, I would like to examine a few types of plugs that can be used with generators. A generator will typically have 20 Amp and 30 Amp ratings and at least one locking plug, usually an L5, L10, or L14, with one or two duplex plugs. Some RVs and travel trailers come with TT-30 plugs.

Ensure that the plugs and the cords you are purchasing are compatible both in rating and type. It is crucial because a 20 Amp plug and a 30 Amp socket are not guaranteed to have identical prong configurations.

Installation Procedure: How to Hook Up a Generator to a Breaker Box

Generators are great because they provide power when you need it most. Connecting a generator to your breaker box is a simple process that just takes a few minutes. Some people don’t know how to hook up a generator to a breaker box. The process of hooking up a generator to a breaker box is not that complicated.

If you are looking to install a generator in your home, it is important to check the voltage of the breaker box properly before installing the new power source. The generator should be installed in a location that does not interfere with the function of the household breaker box and the breaker box properly hooked up to the generator. The first step is to shut off the main breaker and open the breaker box.

1. Check the plug size of your generator and make sure the generator’s power cord is compatible with your breaker box.

2. Shut off power to the circuit breaker.

3. Check the voltage at the breaker box with a voltmeter to over sure that there is no current in the breaker box.

4. Locate an unused/spare circuit breaker in your breaker box/panel.

5. Select the generator’s circuit breaker in such a way that the main circuit breaker, as well as the generator circuit breaker, becomes interlock i.e. these two circuit breakers cannot be turned on at the same time. This means only when the main circuit breaker is off then the generator circuit breaker can be turned on.

Figure 3: Interlock between main circuit breaker as well and generator circuit breaker

6. After installing the interlock, connect the other terminal of the generator plug into the generator circuit breaker properly.

7. Turn off all other circuit breakers of the house. Then connect the generator male to the female plug. 

When you’re ready to turn on the generator, make sure that all the breakers are in the “off” position. Then start the generator and turn on the individual circuit breaker of the house and you will get the power from the generator.