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How To Wire A Motion Sensor To An Existing Light


When it comes to home improvement projects, ensuring the safety and security of your family and property is always a top priority. That’s why many homeowners in the zip code 02904 of North Providence, Rhode Island, rely on B&K Electric for their electrical needs. As a family-owned and operated business based in Warwick, RI, B&K Electric has been providing reliable and efficient electrical services for over seventeen years. Specializing in electrical repair, panel maintenance, and installation, B&K Electric is the go-to electrician for homes and businesses in the Warwick area and greater Providence area.

One of the most common requests from homeowners is to install motion sensor lights for added security. Motion sensor lights are an effective deterrent against burglars and also provide convenience by automatically turning on when someone approaches the property. But what if you already have existing lights in your home and you want to upgrade them to motion sensor lights? In this article, we will discuss how to wire a motion sensor to an existing light, from the perspective of a homeowner.

Understanding Motion Sensor Lights

Before we dive into the specifics of wiring a motion sensor to an existing light, it is important to have a basic understanding of how these lights work. A motion sensor light has a built-in sensor that detects infrared energy emitted by moving objects. When the sensor is triggered, it sends a signal to the light fixture, causing it to turn on. Most motion sensor lights also have a timer that keeps the light on for a certain amount of time.

Choosing the Right Motion Sensor for Your Existing Light

The first step in installing a motion sensor to an existing light is to choose the right motion sensor. There are two types of motion sensors: hardwired and wireless. Hardwired motion sensors require a connection to your home’s electrical system, while wireless sensors run on batteries. If your existing light is already hardwired, it is recommended to choose a hardwired motion sensor for ease of installation. However, if your existing light is not wired, a wireless motion sensor would be a better option.

Tools and Materials Needed

Once you have chosen the right motion sensor, you will need some tools and materials to complete the installation. These include:

– A motion sensor light kit

– A screwdriver

– Wire strippers

– Wire nuts

– Electrical tape

– A ladder (if the light is located high up)

– Electrical gloves for safety

– A voltage tester (optional)

Steps to Wire a Motion Sensor to an Existing Light

Step 1: Turn off the Power

Safety should always be your top priority when working with electricity. Before starting the installation, turn off the power to the existing light at the circuit breaker. Double-check the power is off by using a voltage tester.

Step 2: Remove the Existing Light Fixture

With the power turned off, remove the existing light fixture from the junction box. Carefully disconnect the wires from the fixture and set it aside.

Step 3: Install the Motion Sensor Bracket

If your motion sensor came with a bracket, install it on the junction box according to the manufacturer’s instructions. This may involve connecting the wires from the junction box to the bracket using wire nuts.

Step 4: Connect the Wires

Now it’s time to connect the wires from the motion sensor to the existing wires in the junction box. Match the black wire from the sensor to the black wire from the junction box and twist them together, securing them with a wire nut. Repeat the process for the white wires and the green or copper ground wires.

Step 5: Mount the Sensor and Test It

With the wires connected, mount the motion sensor onto the bracket and tighten the screws. Turn the power back on at the circuit breaker and test the light. Walk in front of the sensor to make sure it is working properly.

Step 6: Adjust the Settings

Most motion sensor lights come with adjustable settings for sensitivity, timer length, and range. Adjust these settings according to your preferences.

Step 7: Cover the Sensor and Secure the Wires

Finally, cover the sensor with the supplied hood or cover and secure any loose wires with electrical tape. This will protect the sensor from outdoor elements and ensure the wires are not exposed.

Concluding remarks

Wiring a motion sensor to an existing light is a simple and effective way to enhance the security of your home and provide added convenience. However, if you are not comfortable working with electricity, it is always best to hire a licensed electrician like B&K Electric for the job. With their expertise and experience, you can have peace of mind knowing your motion sensor lights are installed correctly and safely. Contact B&K Electric today for all your electrical needs.


Motion sensor,

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