Understanding How to Wire a 5 Pin Relay Switch Diagram is a fundamental skill for anyone working with automotive electronics, industrial machinery, or even some home automation projects. These versatile components act as electronic switches, allowing a low-current circuit to control a high-current circuit, thus protecting sensitive components and enabling more complex electrical setups. This guide will walk you through the essential steps to correctly wire a 5-pin relay switch diagram.
Understanding the 5 Pin Relay Switch Diagram
A 5-pin relay switch, often referred to as a changeover relay, is a crucial component that allows you to switch a load between two different circuits. At its core, it's an electromagnetically operated switch. When a small voltage is applied to its coil, it creates a magnetic field that physically moves an internal contact, thus switching the flow of current. This ability to control higher power circuits with a low-power signal is incredibly important for safety and efficiency .
The five pins on a typical relay have specific functions:
- 85: Coil - Negative (Ground): This is where the negative side of the control circuit connects.
- 86: Coil - Positive (+12V or control voltage): This pin receives the positive voltage from the control switch or signal that energizes the relay coil.
- 30: Common (Input): This is the common terminal. When the relay is not energized, it's connected to pin 87. When energized, it switches to pin 87a.
- 87: Normally Open (NO): This terminal is connected to pin 30 only when the relay coil is energized. This is used to switch on a device when the relay is active.
- 87a: Normally Closed (NC): This terminal is connected to pin 30 only when the relay coil is *not* energized. This is used to switch off a device when the relay is active or keep a device on by default.
Here's a breakdown of common applications and how the diagram works:
- Accessory Power: You can use a 5-pin relay to power accessories like fog lights or an aftermarket stereo. The low-current switch in your dashboard energizes the relay coil (pins 85 & 86), which then connects battery power (pin 30) to the accessory (pin 87).
- Dual Functionality: The "changeover" aspect means you can have a load that is either on or off by default. For example, you could have a warning light that is normally on (connected to 87a) and turns off when the relay is activated (circuit to 87).
- Protection: By using a relay, you isolate the higher current drawn by a device from the lower current of your control switch, preventing damage to the switch and wiring.
| Relay State | Pin 30 to Pin 87 | Pin 30 to Pin 87a |
|---|---|---|
| De-energized (Coil OFF) | Open | Connected |
| Energized (Coil ON) | Connected | Open |
Now that you have a solid understanding of the components and their roles, it's time to put this knowledge into practice. For a visual and step-by-step walkthrough of wiring your 5-pin relay, refer to the detailed diagrams and instructions provided in the next section.