How To Replace A Motion Sensor For Outdoor Lights

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How To Replace A Motion Sensor For Outdoor Lights

Welcome back! Today we’re going to show you how to wire multiple exterior lights to one motion sensor—a useful setup for lighting up large outdoor areas like driveways, backyards, or commercial buildings.

Let’s dive in.

Overview of the Setup

In this example, we’re working with:

  • Two large 150-watt LED lights
  • One central motion sensor mounted in a weatherproof RAB box

This configuration allows both lights to be controlled by a single motion sensor, turning them on simultaneously when movement is detected.

How It’s Wired

The wiring is straightforward but must follow a specific logic to work correctly and safely:

  1. Power Source
    • Power comes in through a piece of 14/2 wire (120V).
    • This wire feeds into the central box containing the sensor.
  2. Neutral Wires (White)
    • All neutral wires from the power source, sensor, and both lights are connected together.
    • This creates a shared return path for current.
  3. Hot Wire (Black) to the Sensor
    • The black wire from the power source connects to the black wire on the motion sensor.
    • This provides the sensor with a constant power supply.
  4. Switched Hot Wire (Red) from the Sensor
    • The red wire from the sensor is the “switched hot.”
    • It connects to the black wires leading to the lights.
    • When motion is detected, the sensor sends power through this wire to turn on the lights.
  5. Wiring Between Boxes
    • A short length of conduit (pipe) is used to route wires from the sensor box to each of the light boxes on either side.

Important Load Considerations

Before you start wiring up multiple lights, always check the load rating of your sensor:

  • The sensor used here is rated for 200 watts maximum.
  • Each light was originally 150 watts, but these were selectable wattage models.
  • We adjusted them down to 100 watts each to stay under the sensor’s load limit.

Tip: Not all sensors specify if their load rating is for incandescent or LED, so it’s safer to check the documentation or contact the manufacturer if in doubt.

Motion Testing

Once wired correctly:

  • The lights should turn on when motion is detected
  • They will turn off automatically after a set amount of time when motion ceases

Everything worked smoothly during our test, and we confirmed the sensor reacted as expected.

Final Thoughts

You can wire as many lights as you’d like to a single motion sensor as long as you stay under the sensor’s rated wattage. For example, you could wire six LED fixtures if each is only drawing 25 watts—just do the math and never exceed the sensor’s capacity.

Basic Rule of Thumb:

  • Black wire from power → to black wire on sensor
  • Red wire from sensor → to black wires on the lights
  • All neutrals tied together

That’s it! We hope this helped you understand how to control multiple outdoor lights from one sensor. Don’t forget to like and subscribe, and we’ll see you next week with another project.

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