LED lights have become more and more popular in the last couple of years. They are energy-efficient and perfect for indoor and outdoor lighting. If you want to install LED lights in your car, boat or RV, you need to know how to wire them properly. One of the most common ways to do it is by using a relay. In this article, we will explain how to wire a 12 volt LED with a relay and provide you with a wiring diagram.
What is a Relay?
A relay is an electronic component that allows you to switch a high-current load (like a light) with a low-current signal (like a switch). It’s like an electrically operated switch that can handle large amounts of current. Relays are used in many applications, including automotive, boats, and off-road vehicles.
How Does a Relay Work?
A relay consists of an electromagnet, a switch, and a spring-loaded contact. When an electrical current passes through the coil of the electromagnet, it creates a magnetic field that pulls the contact towards the electromagnet. This allows current to flow through the switch, activating the load that is connected to it. When the current is turned off, the spring pulls the contact back to its original position, switching off the load.
Why Use a Relay with LED Lights?
LED lights are sensitive to heat and voltage fluctuations. If you wire them directly to your battery or your switch, they may not work properly or even get damaged. Using a relay can help to protect your LED lights and prevent them from flickering or burning out.
Wiring a 12 Volt LED with a Relay
To wire an LED light with a relay, you will need the following:
- A 12 volt LED light
- A relay
- A switch
- A fuse (optional but recommended)
- A wiring harness with connectors and terminals
Follow these steps to wire your LED light:
- Mount your LED light in the desired location and run the wiring back to where you want to install your switch.
- Connect the positive (+) wire of your LED light to pin 87 of your relay. Pin 87 is the normally open (NO) contact of the relay.
- Connect the negative (-) wire of your LED light to a good ground. This can be any bare metal on your vehicle or a dedicated grounding point.
- Run a wire from pin 86 of your relay to one side of your switch. This will be the low-current signal that activates your relay.
- Run another wire from the other side of your switch to a 12-volt power source. This can be your battery or an accessory circuit that is only on when the key is turned on.
- Install a fuse in-line with the wire that runs from your switch to your power source. This will protect your wiring in case of a short circuit.
- Finally, connect pin 85 of your relay to a good ground. This completes the circuit and allows your relay to work properly.
Once you have completed these steps, test your LED light by turning on your switch. If everything works properly, you should have a bright and energy-efficient light.
Wiring Diagram
Here is a wiring diagram that shows how to wire a 12 volt LED with a relay:
| Terminal | Connection |
| 85 | Ground |
| 86 | Switched 12v |
| 87 | LED Light Positive (+) |
| 30 | Battery Positive (+) with Fuse |
Make sure to follow the wiring diagram closely and use the right terminals and connectors for your wiring harness.
FAQ
Can I use a relay with any LED light?
Yes, you can use a relay with any LED light as long as it requires a 12-volt power source. The wiring procedure is the same for all LED lights.
Do I need to install a fuse?
It’s recommended to install a fuse in-line with the wire that runs from your switch to your power source. This will protect your wiring in case of a short circuit.
Can I use a different type of switch?
Yes, you can use a different type of switch as long as it’s compatible with your relay and your wiring harness.
Can I use a relay to control multiple LED lights?
Yes, you can use a relay to control multiple LED lights as long as the total current draw doesn’t exceed the rating of your relay.
Can I wire my LED lights directly to my battery?
Yes, you can wire your LED lights directly to your battery, but it’s not recommended. LED lights are sensitive to voltage fluctuations, and wiring them directly to your battery can cause them to flicker or burn out. Using a relay can help to protect your LED lights and ensure that they work properly.
