Relay wiring can be a complex task, but it’s essential to know how to get it done right. In this article, we will be discussing relay wiring diagrams for 4 pin relays. This topic will cover the basics of what relays are, how they work, and how to wire them for your specific needs.
What Are Relays?
Relays are electrical devices that operate like switches. Typically, they are used to control high voltage or high current circuits using low voltage or low current circuits. Relays consist of two main parts: the coil and the contacts. The coil is what creates the magnetic field that closes the contacts, which then allows current to flow through the circuit.
Relays can be used in a variety of applications, including automotive, industrial, and residential. They are often used in automotive applications to control things like lights, fans, and other electrical systems. In industrial applications, relays can be used to control equipment or machines, while in residential settings, they can be used to control heating and cooling systems or lighting.
How Do Relays Work?
When a low voltage or low current is applied to the relay coil, it creates a magnetic field that moves the contacts. This allows current to flow through the circuit, which activates the device that the relay is controlling. When the voltage or current is removed from the coil, the magnetic field collapses, and the contacts return to their original state, which interrupts the current flow.
Relays come in various types, including single-pole, double-pole, single-throw, double-throw, and 4-pin relays. In this article, we will be focusing on 4-pin relays and their wiring diagrams.
4 Pin Relay Wiring Diagram
A 4 pin relay is typically used when you need to switch a low current circuit on or off using a high current circuit. These relays have four pins or terminals on them, and each one has a specific function. The pins are typically labeled “30”, “85”, “86”, and “87”. Here is a basic wiring diagram for a 4 pin relay:
| PIN | FUNCTION |
|---|---|
| 30 | Power (from power source to relay) |
| 85 | Trigger (from switch or computer) |
| 86 | Ground (connect to chassis or ground) |
| 87 | Output (to device being controlled) |
Pin 30 is the power input to the relay, and it should be connected to a power source that is capable of handling the load being controlled. Pin 85 is the trigger input, which comes from a switch or computer. Pin 86 is the ground, which should be connected to the chassis or ground. Finally, pin 87 is the output, which goes to the device being controlled.
When the trigger input (pin 85) is activated, the relay coil creates a magnetic field, which pulls the contacts closed. This completes the circuit between pins 30 and 87, which allows current to flow to the device being controlled.
FAQs
What is the function of a 4 pin relay?
A 4 pin relay is used to switch a low current circuit on or off using a high current circuit.
How do you wire a 4 pin relay?
A 4 pin relay should be wired according to its specific wiring diagram. Typically, pin 30 is the power input, pin 85 is the trigger input, pin 86 is the ground, and pin 87 is the output to the device being controlled.
What are some common uses for a 4 pin relay?
4 pin relays are commonly used in automotive applications to control things like lights, fans, and other electrical systems. They are also used in industrial and residential settings to control equipment or machines, heating and cooling systems, and lighting.
What is the difference between a 4 pin and 5 pin relay?
4 pin and 5 pin relays differ in the number of pins they have. 4 pin relays have four terminals, while 5 pin relays have five. The additional pin on a 5 pin relay is typically used for a second trigger input or for a feedback signal.
Can you use a 4 pin relay for a high current circuit?
Yes, a 4 pin relay can be used for a high current circuit as long as the power input (pin 30) and the output (pin 87) are rated for the current being used.
Conclusion
Relay wiring diagrams can be confusing, but understanding the basics can help you get it done right. In this article, we discussed 4 pin relay wiring diagrams, which are commonly used in automotive, industrial, and residential applications. Remember to always refer to the specific wiring diagram for your relay to ensure proper installation.
