Relays are important components of electrical systems. They allow low voltage signals to control high voltage circuits. The 87a relay is a type of relay that is commonly used in automotive applications. This journal article will cover everything you need to know about the 87a relay wiring diagram.
What is an 87a relay?
The 87a relay is a type of electromagnetic switch. It is designed to allow low current signals to control high current loads. When the relay receives a signal, it closes a set of contacts that allows current to flow to the load. The 87a relay is commonly used in automotive applications to control lights, fans, and other electrical devices.
The 87a relay is typically a single pole, double throw (SPDT) relay. This means that it has one normally open (NO) contact, one normally closed (NC) contact, and one common (COM) contact. When the relay is not energized, the NO contact is open and the NC contact is closed. When the relay is energized, the NO contact closes and the NC contact opens.
Wiring an 87a relay
The 87a relay is typically wired with four connections: power, ground, signal, and load. The power connection is connected to a constant source of voltage, such as the battery. The ground connection is connected to the vehicle’s chassis. The signal connection is connected to the input signal that will control the relay, such as a switch or a computer. The load connection is connected to the device that the relay will control, such as a light or a fan.
When the signal connection is energized, the relay closes the NO contact and opens the NC contact. This allows current to flow from the power connection to the load connection. When the signal connection is de-energized, the relay opens the NO contact and closes the NC contact. This stops the flow of current to the load connection.
87a relay wiring diagram
The 87a relay wiring diagram can be represented in a schematic form. This diagram shows each of the connections and how they are wired together. The 87a relay wiring diagram typically includes a symbol for the relay, as well as symbols for the power, ground, signal, and load connections.
| Connection | Symbol | Color |
|---|---|---|
| Power | Battery | Red |
| Ground | Chassis | Black |
| Signal | Switch | Green |
| Load | Light | Yellow |
The 87a relay wiring diagram can be used as a reference when wiring an 87a relay. It shows how the connections should be made and the colors of the wires that are typically used.
FAQ
What is the difference between a NO and NC contact?
A normally open (NO) contact is open when the relay is not energized and closes when the relay is energized. A normally closed (NC) contact is closed when the relay is not energized and opens when the relay is energized. The 87a relay has both a NO and NC contact.
What is the purpose of an 87a relay?
The purpose of an 87a relay is to allow low voltage signals to control high voltage circuits. It is commonly used in automotive applications to control lights, fans, and other electrical devices.
What is a single pole, double throw (SPDT) relay?
A single pole, double throw (SPDT) relay has one common (COM) contact, one normally open (NO) contact, and one normally closed (NC) contact. When the relay is not energized, the NO contact is open and the NC contact is closed. When the relay is energized, the NO contact closes and the NC contact opens.
What is a schematic diagram?
A schematic diagram is a diagram that shows the connections between components in an electrical system. It uses symbols to represent each component and lines to represent the connections between the components.
What colors are typically used for power, ground, signal, and load connections?
The color of the wires used for power, ground, signal, and load connections can vary depending on the application. In automotive applications, red is typically used for power, black is typically used for ground, green is typically used for signal, and yellow is typically used for load.
Conclusion
The 87a relay is an important component of automotive electrical systems. It allows low voltage signals to control high voltage circuits. When wiring an 87a relay, it is important to follow the wiring diagram and use the correct colors for each connection. By understanding the 87a relay wiring diagram, you can ensure that your electrical system works properly and reliably.
