A relay is an electrically operated switch used to control high power devices without any physical contact with the controlling circuit. A four prong relay is a type of relay that is used in automotive applications to control electrical circuits. In this article, we will guide you on how to wire a four prong relay with the help of a wiring diagram, along with its uses, specifications, and benefits.
What is a Four Prong Relay?
A four prong relay is a type of relay that has four terminals, which are numbered 30, 85, 86, and 87. The terminal numbers are usually printed on the plastic case of the relay. The 30 and 87 terminals are the main contacts of the relay that can switch a high current load, while 85 and 86 terminals are the control circuit terminals.
The four prong relay is widely used in automotive applications, such as controlling headlights, horn, fuel pump, and other electrical devices. The relay can be wired with the help of a wiring diagram, which is discussed in detail in the next section.
How to Wire a Four Prong Relay?
Wiring a four prong relay is a simple process, and it can be done with the help of a wiring diagram. The following steps will guide you on how to wire a four prong relay:
Step 1: Gather the Required Tools
Before you start wiring a four prong relay, you need to gather the required tools, which include:
| Tools | Quantity |
|---|---|
| Screwdriver | 1 |
| Wire stripper | 1 |
| Electrical tape | 1 roll |
| Wire connectors | 4 |
| Four prong relay | 1 |
Step 2: Identify the Relay Terminals
Identify the relay terminals with the help of the terminal numbers printed on the plastic case of the relay. The 30 and 87 terminals are the main contacts of the relay, while 85 and 86 terminals are the control circuit terminals.
Step 3: Connect the Control Circuit Wires
Connect the control circuit wires to the 85 and 86 terminals of the relay. The control circuit wires can be connected using wire connectors.
Step 4: Connect the High Current Load Wires
Connect the high current load wires to the 30 and 87 terminals of the relay. The high current load wires can be connected using wire connectors.
Step 5: Insulate the Connections
Insulate the connections with the help of electrical tape to prevent any short circuits.
Now your four prong relay is wired, and it is ready to control electrical circuits.
FAQ
What is the Purpose of a Four Prong Relay?
A four prong relay is used to control electrical circuits in automotive applications, such as headlights, horn, fuel pump, and other electrical devices.
What are the Benefits of Using a Four Prong Relay?
The benefits of using a four prong relay are:
- Can switch high current loads without any physical contact with the controlling circuit
- Provides safety to the controlling circuit
- Increases the lifespan of the controlling circuit
- Can be easily wired with the help of a wiring diagram
What is a Wiring Diagram?
A wiring diagram is a graphical representation of an electrical circuit. It shows the components of the circuit as simplified shapes, and the power and signal connections between the devices.
What is the Difference Between a Four Prong Relay and a Five Prong Relay?
A four prong relay has four terminals, while a five prong relay has five terminals. The fifth terminal in a five prong relay is used for additional functions, such as a diode, resistor, or capacitor.
How Can I Test a Four Prong Relay?
You can test a four prong relay with the help of a multimeter. Connect the multimeter to the control circuit terminals (85 and 86), and apply voltage to the control circuit terminals. The multimeter should show continuity between the main contact terminals (30 and 87).
Conclusion
A four prong relay is a simple and efficient way to control high current loads without any physical contact with the controlling circuit. Wiring a four prong relay is a simple process, and it can be done with the help of a wiring diagram. The four prong relay is widely used in automotive applications, such as controlling headlights, horn, fuel pump, and other electrical devices.
With the help of this ultimate guide, you can easily wire a four prong relay and control electrical circuits in your automotive applications.
