A photocell is a mechanism that functions in the same way as an electric switch on outdoor lights. When the photocell senses ambient light, the photocell turns off the photocell-controlled lights. Often, you see these on outdoor security lights. In addition, you can have multiple outdoor lights and light fittings running from one photocell, as long as they are connected to the same line.
Because of the numerous advantages that photocells provide, they are in high demand to control multiple lights as the photocell switches automatically save electricity and reduce light pollution. In our guide, you can learn more about adding more light fittings using a photocell with no photocell wiring diagram with contactor.
By the end, you’ll know the total number of lights you can have on your circuits that most photocells can deal with. (Learn How To Hang String Lights In Backyard Without Trees)
Can One Photocell Control Multiple Lights?
You can have other lights controlled by one photocell, yet there are a few things to understand before loading wire with light fittings.
To add a photocell to many outdoor lights, you must first determine the number of lights installed, the circuit, where the power will come from, and how to attach conduit pipes and cables.
Number of Lights
The first thing you should do is figure out how many lights you’ll need. This helps determine the right size of the photocell to use.
Keep in mind that most photocells have a wattage rating, which dictates how many lights a photocell switch can operate.
Number of Circuits
You’ll also need to figure out how many circuits you’ll require. To do so, count the number of lights you have and determine their power rating.
Next, figure out how much current each light will draw from the power supply. If you have more light fixtures than a circuit breaker can handle, you’ll need to use a different circuit to supply them.
Source of Energy
The next step is to choose a power source. Again, avoid using the current indoor lighting circuits for power. This is particularly problematic if you have a large number of outside security lights to install. (Find Outdoor Battery Operated String Lights)
Making a separate circuit for the lights controlled by a photocell is the best thing you can do.
How Do You Wire a Photocell Circuit?
Outdoor lighting fixtures frequently feature photocell switches. Luckily, a photocell switch sensor is straightforward to install. In addition, these help you save money on your electric bill.
The steps for wiring a photocell switch sensor are outlined below.
- The first step is to turn off all electrical power to the light fixture where you wish to install the photocell.
- Using a screwdriver, remove the light from the electrical box.
- Remove the two wire nuts that connect the wires to the light fixture and power supply. Ensure your light fixture is installed on a flat surface for easy installation.
- The connecting hole needs removing, which is located at the front of the outdoor lighting fixtures. Place the screwdriver’s tip in the knockout hole and strike the other end of the screwdriver with wire pliers to remove the metal knockout cover.
- Insert the photocell’s metal end into the hole.
- Use the small lock nut from the back of the lighting fixture to tighten the switch, and tighten the nut using your wire pliers.
- The photocell switch will connect using three wires—the switch’s white neutral wire. The black cable is the main power source for the photocell switch, and the switch wire coming from the photocell is the red wire.
- Now, it’s time to connect your wires. First, twist the three white neutral wires together with a wire nut, and ensure you cover the bare copper ends.
- Connect the photocell switch’s black wire to the black wire from the fixture’s electrical box, which is the power source.
- Cover the wires using a wire nut after twisting them together to lock them in place.
- Connect the photocell’s red wire to the black wire attached to the light fixture.
- The last step is to connect the lighting fixture to the electrical box. Finally, ensure you replace the light fixture’s light bulb.
How Do You Wire A Photocell To A Switch?
Here are the steps you need to connect a photocell to a lighting contactor; wiring diagram with photocell may be required if you are new to installing outdoor lights.
When you have many lights, a photocell switch will not be enough. To turn on the lights, you’ll need the help of a contactor, which acts as your manual switch.
How does a photocell and a contactor operate together? A contactor is a small-current-actuated magnetic switch. Instead of using a photocell to handle the full load of the lights, the circuit breaker’s contactor supplies power to the switch wire attached to the lights.
You connect the circuit breaker in the consumer unit to the contactor via an electrical cable.
Two things need to be followed here. First, avoid using the same circuit as any existing indoor lighting circuits; second, you’ll need to install electrical conduit pipes.
Electrical conduit piping prevents wires from getting wet and protects them when you dig in your garden or mow your lawn. (Read Light Bulb Base Chart)
Additionally, how many lights you can run will depend on the power rating of your photocell and contactor.
For example, if you have three circuits, you’ll run three cables from the DB to the contactor.
- The cables from the DB are connected to the contactor terminals labeled L1, L3, and L5.
- The supply wires are connected to the main contactor contacts.
- Connect the cords leading to the lights to the L2, L4, L6 terminals.
- Connect the photocell cable to the terminal labeled A1 on the contactor and the neutral wire to the terminal labeled A2.
- In this circuit, the photocell’s purpose is to energize the contactor.
- The lights are turned on when the contactor is activated.
Once you know how many lights you’ll have on the same circuit, and how many other lights on another circuit, it gets easier to know where to run your conduit pipes.
How to wire a photocell overview:
To get a clear picture of the connectors used on a photocell used in lighting applications, they have three terminals labeled as:
- Load line (Lo)
- Neutral line (N)
- Supply or live line (LI)
In most photocells, the load line wire is “red,” the neutral wire is “white,” and the Supply line is “black,” as you could see in a 3 wire photocell diagram.
This colour code won’t be universal and can change between one photocell brand and other photocells. (Read 100 Amp Service Wire Size Guide)
Do Photocells Need A Neutral?
Like any other electronic equipment requiring a modest electric current to operate, there must be a way of returning a current to a neutral line.
When the load is to control multiple lights, the little current could be dumped to neutral through the load without you knowing, allowing photo switches to operate with simply line and load connections.
Although the loads may now be LED outdoor lights, the low operating current poses issues, particularly with lamps that flash.
Because of this, most modern photo switches contain a neutral connection to discharge an operational current to neutral instead of passing through the load.