Relays are an essential part of many electrical systems. They act as a switch that opens and closes a circuit. They are commonly used in automotive applications, such as controlling headlights, starting motors, and powering fuel pumps. A 4-way relay is a type of relay that has four pins or terminals. In this article, we will discuss the 4-way relay wiring diagram and how to connect it properly.
What is a 4 Way Relay?
A 4-way relay is a type of relay that has four pins or terminals. It is also known as a 4-pin relay. The four pins are usually labeled as follows:
- Pin 30: This is the common pin, which is connected to the power source.
- Pin 85: This is the trigger pin, which is connected to the switch or controller that activates the relay.
- Pin 86: This is the ground pin, which is connected to the ground.
- Pin 87: This is the output pin, which is connected to the device that the relay is controlling.
The 4-way relay is designed to handle low-current and high-current applications. It can be used for a variety of purposes, from turning on a light to starting an engine.
How to Connect a 4 Way Relay
Connecting a 4-way relay is relatively easy. The following steps outline the process:
- Identify the pin layout: The pin layout can vary depending on the specific type of relay you have. Make sure you understand how the pins are labeled before attempting to connect the relay.
- Connect pin 30: Connect pin 30 to the power source. This is usually the positive terminal on the battery or an auxiliary power source.
- Connect pin 85: Connect pin 85 to the switch or controller that will activate the relay. This is usually a low-current source, such as a switch or sensor that sends a signal to the relay.
- Connect pin 86: Connect pin 86 to the ground. This is usually the negative terminal on the battery or chassis ground.
- Connect pin 87: Connect pin 87 to the device that the relay is controlling. This can be anything from a light bulb to an electric motor.
Once you have connected the relay, test it to make sure it is functioning properly. You can use a multimeter to check the voltage and continuity of the connections.
4 Way Relay Wiring Diagram
The following 4-way relay wiring diagram shows how to connect a 4-pin relay in a typical automotive application:
| Pin | Description | Connection |
| 30 | Common | Positive (+) |
| 85 | Trigger | Switch or Controller |
| 86 | Ground | Negative (-) |
| 87 | Output | Device |
The wiring diagram shows how to connect the 4-way relay to a switch and a light bulb. When the switch is turned on, it sends a signal to the relay’s trigger pin (pin 85), which activates the relay. The relay then closes the circuit, sending power to the light bulb through pin 87.
FAQs
What is the difference between a 4-way relay and a 5-way relay?
The main difference between a 4-way relay and a 5-way relay is the number of pins. A 5-way relay has five pins, while a 4-way relay has only four. The additional pin on a 5-way relay is usually used for a feedback signal or to control a secondary device.
Can I use a 4-way relay for high-current applications?
Yes, a 4-way relay can be used for high-current applications. However, you need to make sure that the relay is rated for the amount of current that will be flowing through it. Check the manufacturer’s specifications to determine the maximum current rating of the relay.
What are some common applications of a 4-way relay?
A 4-way relay can be used for a variety of applications, including:
- Controlling headlights in a car
- Starting motors in industrial equipment
- Powering fuel pumps in boats
- Turning on/off lights in a home automation system
What happens if I connect the relay incorrectly?
If you connect the relay incorrectly, it may not function properly or it may cause damage to the electrical system. Always double-check the pin layout before connecting the relay and test it thoroughly before putting it into use.
Where can I buy a 4-way relay?
A 4-way relay can be purchased from an electronics store, automotive supply store, or online retailer. Make sure to check the specifications to ensure that it is compatible with your application.
