Emergency backup: learn how to wire a portable generator to your breaker box in 5 easy steps

In the wake of power outages caused by natural disasters or grid failures, having a portable generator can provide much-needed backup power for your home. However, connecting a portable generator to your electrical system safely requires proper wiring to your breaker box. Follow these detailed instructions to ensure a secure and efficient connection.

Safety Precautions

Before beginning any electrical work, it is crucial to prioritize safety. Always wear protective gear, including gloves and safety glasses. Turn off the main breaker in your breaker box and disconnect the utility power line from your home. Never connect a generator to a live circuit.

Materials Required

• Portable generator
• Generator interlock kit
• Heavy-duty extension cord (rated for outdoor use)
• Wire nuts
• Electrical tape
• Screwdriver

Step 1: Choose the Correct Interlock Kit

A generator interlock kit is a specialized device that prevents back-feeding, which occurs when electricity from the generator flows back into the utility grid. This can be extremely dangerous for utility workers and can damage your generator. Select an interlock kit compatible with your breaker box.

Step 2: Install the Interlock Kit

Follow the manufacturer’s instructions to install the interlock kit in your breaker box. This typically involves removing a knockout plug, inserting the interlock bracket, and connecting the wires. Ensure that the interlock is in the “OFF” position before proceeding.

Step 3: Connect the Generator to the Interlock Kit

Using the heavy-duty extension cord, connect the generator to the inlet on the interlock kit. Tighten the connections with wire nuts and electrical tape.

Step 4: Connect the Generator to the Breaker Box

Open the breaker box and locate the circuit breaker that powers the essential circuits you want to run on the generator. Turn off this breaker.

Step 5: Connect the Interlock Kit to the Breaker Box

Connect the wires from the interlock kit to the terminals on the circuit breaker using wire nuts and electrical tape. Ensure that the connections are secure.

Step 6: Turn on the Generator and Test the Interlock

Start the generator and turn on the circuit breaker connected to the interlock kit. The interlock should automatically switch the power source from the utility grid to the generator.

Step 7: Turn on Essential Circuits

Turn on only the essential circuits you need to power with the generator. Do not overload the generator.

How to Disconnect the Generator

• Turn off all circuits connected to the generator.
• Turn off the generator.
• Turn the interlock kit to the “OFF” position.
• Disconnect the extension cord from the interlock kit.
• Reconnect the utility power line to your home.
• Turn on the main breaker in your breaker box.

Tips for Safe Generator Use

• Never operate a generator indoors.
• Keep the generator dry and protected from the elements.
• Use a properly sized generator for your needs.
• Ground the generator properly.
• Avoid overloading the generator.
• Monitor the generator’s fuel level regularly.
• Have a carbon monoxide detector near the generator.

Questions You May Have

Q: Can I wire a portable generator to my breaker box without an interlock kit?
A: No, it is extremely dangerous to wire a generator to your breaker box without an interlock kit. This could result in back-feeding, which can harm utility workers and damage your generator.

Q: What size extension cord do I need to connect my generator to the breaker box?
A: Use a heavy-duty extension cord rated for outdoor use and sized appropriately for the wattage of your generator.

Q: How often should I test my generator interlock kit?
A: It is recommended to test your generator interlock kit monthly by starting the generator and verifying that the power source switches from the utility grid to the generator.