An automotive relay is a switch that is controlled by an electrical circuit. It is typically used to control a high-power circuit with a low-power signal, such as the signal from a switch or a sensor. The 12 volt automotive relay wiring diagram is a diagram that shows how the wiring for a 12 volt automotive relay should be connected.
What is a Relay?
A relay is an electrical switch that is operated by an electromagnet. When the electromagnet is energized, it pulls a lever or armature that closes or opens a set of contacts. The contacts can be normally open (NO) or normally closed (NC), and they can be rated for different voltages and currents.
Relays are used in many different applications, from controlling lights and fans to starting and stopping motors and controlling solenoid valves. They are also used in automotive applications, such as controlling the headlights, air conditioning, and starter motor.
How Does a Relay Work?
A relay works by using an electromagnet to close or open a set of contacts. The electromagnet is energized by a low-power signal – such as the signal from a switch or a sensor – and it pulls a lever or armature that closes or opens the contacts.
When the contacts are closed, the high-power circuit is completed and the load – such as the headlight or motor – is turned on. When the contacts are opened, the high-power circuit is interrupted and the load is turned off.
Types of Relays
There are many different types of relays, including:
- Electromechanical relays
- Solid state relays
- Latching relays
- Reed relays
- Polarized relays
Each type of relay has its own advantages and disadvantages, and is suited for different applications.
The 12 Volt Automotive Relay Wiring Diagram
The 12 volt automotive relay wiring diagram shows how a relay should be wired in a typical automotive application. The diagram includes the following components:
The wiring diagram shows how the switch is connected to the relay, and how the relay is connected to the battery and the load.
How to Read the Wiring Diagram
The wiring diagram consists of symbols and lines that represent the different components and connections. Here are some tips for reading the wiring diagram:
- The relay is represented by a rectangle with two smaller rectangles inside it.
- The switch is represented by a single line with an arrowhead at one end.
- The battery is represented by a rectangle with a plus (+) and minus (-) sign inside it.
- The load is represented by a rectangle with an arrowhead pointing away from it.
The lines connecting the components represent the wires. The diagram shows how the wires should be connected to complete the circuit.
How to Wire a 12 Volt Automotive Relay
Wiring a 12 volt automotive relay is a simple process. Here are the steps:
- Connect the positive (+) terminal of the battery to terminal 30 on the relay.
- Connect the positive (+) wire from the load to terminal 87 on the relay.
- Connect the negative (-) wire from the battery to the switch.
- Connect the negative (-) wire from the switch to terminal 86 on the relay.
- Connect a wire from terminal 85 on the relay to a ground point on the vehicle.
Once the wiring is complete, the circuit can be tested by activating the switch. When the switch is activated, the relay should close and power should be applied to the load.
What is the purpose of a relay in an automotive application?
A relay is used in an automotive application to control a high-power circuit with a low-power signal. For example, a relay may be used to control the headlights or the starter motor. The low-power signal comes from a switch or a sensor, and the relay is used to switch the high-power circuit on and off.
How do I know if my automotive relay is bad?
If your automotive relay is bad, it may not switch on or off when it should. This can cause the load – such as the headlights – to not function properly. You can test the relay by using a multimeter to check the resistance of the contacts. If the resistance is higher than the specified value, the relay may be bad and should be replaced.
What is the difference between a NO and NC relay?
A NO (normally open) relay has contacts that are open when the relay is not energized, and close when the relay is energized. An NC (normally closed) relay has contacts that are closed when the relay is not energized, and open when the relay is energized.
Can I use a 24 volt relay on a 12 volt system?
No, you cannot use a 24 volt relay on a 12 volt system. The relay is rated for a specific voltage, and using a relay that is not rated for the voltage of the system can cause damage to the relay and the other components in the system.
What is a solid state relay?
A solid state relay (SSR) is a type of relay that uses electronic components – such as transistors and diodes – instead of mechanical contacts to switch the circuit on and off. SSRs are typically faster and more reliable than electromechanical relays, and they can handle higher frequencies and currents.
The 12 volt automotive relay wiring diagram is an important tool for anyone working with automotive electrical systems. By following the wiring diagram and understanding how relays work, you can improve the performance and reliability of your automotive systems.