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How To Wire a Photocell to Multiple Lights

Do you want a photocell lighting control for multiple lights? Wiring a photocell to more than one light makes it possible to turn them on and off automatically, depending on the amount of light in your space.

In this post, we will discuss how to wire a photocell to multiple lights in order to create a convenient and energy-efficient lighting system. By using a photocell, you can save money on your energy bills and ensure that your lights are only on when they are needed.

Table of Contents

What is a Photocell and How Does It Work?

A photocell is a mechanism that operates similarly to an electric switch on outdoor lights. When the photocell detects ambient light, it turns off the photocell-controlled lights. They are mostly found on outdoor security lights.

A basic photocell has two terminals that are connected using a resistor. The light hitting the cell creates a resistance change based on its intensity. Photocells are mostly used with devices with an on/off function.

If the device is switched on, the photocell will sense the infrared or visible light and complete the circuit to turn it off. However, if there’s no infrared or visible light, the photocell won’t complete the circuit, and your device will not turn on.

Safety Precautions to Consider When Installing or Using Photocells

How To Wire a Photocell to Multiple Lights
  • Do not use direct current on photocells because they are designed with Alternating Current (AC). Direct current is used on wall outlets and switches.
  • Photocells do not function properly when exposed to direct sunlight, strong magnetic fields, or artificial lighting containing ultraviolet radiation.
  • Don’t use photocells to activate electronic gadgets that need loads above 10 watts or 16 amperes.
  • Do not use photocells as a safety cutout with direct current or exposure. You risk being electrocuted by holding the terminals of a photocell exposed to direct current.
  • Your photocell connection should be below 600 volts unless stated in the photocell manual. Therefore, use the right relays to control high-voltage appliances such as High-Intensity Discharge (HID) lights.
  • Photocells should not be installed outdoors. If you install them indoors, ensure you properly secure them with waterproof materials like plastics and tapes.
  • Always connect photocells to the pilot light’s leads on a device and to the AC power. This will allow lights to turn on without wasting energy.

How To Wire a Photocell to Multiple Lights (Steps)

  • Turn off the power to the circuit where you want to install the photocell.
  • Use a screwdriver to remove the light from the electrical box.
  • Remove the two wire nuts and connect the wires to the power supply and light fixture. Ensure your light fixture is installed on a flat surface for seamless installation.
  • Remove the connecting hole located at the front of the outdoor lighting. Place your screwdriver’s tip in the knockout hole and hit the head of the screwdriver with wire pliers to eliminate the metal knockout cover.
  • Place the photocell’s metal end into the hole.
  • Using the small lock nut from the lighting fixture’s back, tighten the nut using the wire pliers.
  • Your photocell switch should connect using three wires. The red wire is the switch wire coming from the photocell, and the black wire is the power source for your photocell switch.
  • Now, get ready to connect the wires. Start by twisting the three white neutral wires using a wire nut, and cover the bare copper ends.
  • Connect your photocell switch’s black cable to the black wire from the fixture’s power source.
  • Ensure you cover your wires using a wire nut after joining them to lock them in place.
  • Connect the red wire from the photocell to the black wire joined to the light fixture.
  • Finally, connect your lighting fixture to the electrical box. Ensure you replace your light bulbs.

Tips For Maintaining and Troubleshooting the Photocell and Lighting System

  • Ensure that your photocell is facing toward the outside of the house. It will ensure that it will be illuminated with direct sunlight and give maximum luminosity to determine whether or not your lights should be on.
  • Do not buy cheap photocells. You might be inviting trouble into your house. Invest in a high-quality photocell that will be durable and give efficient outcomes.
  • If your photocell is outdoors, ensure it’s protected from debris or bad weather that could trigger the lights when they are not supposed to be on.


Do Photocells Need a Neutral?

Like most electrical devices using a modest electric current to function, they must have a way of returning a current o a neutral line. Most modern photocells have a neutral connection to release an operational current to neutral instead of passing through the load.


Photocells are crucial devices you can use to comfortably and remotely control multiple indoor and outdoor lights in your home. I hope this article will help you to connect a photocell to your favorite light fixture.

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