A relay is an electrically operated switch which uses an electromagnet to mechanically operate a switch. Relays are used where it is necessary to control a circuit by a separate low-power signal, or where several circuits must be controlled by one signal. For example, if you want to control an AC bulb using evive, you have to use a relay. Similarly, it is used in high current applications.
Relay operating at 5V can be directly used with evive using its digital pins. Given below is the circuit for controlling an AC bulb using relay:
We are using Keyes 5V Relay Module. It has three pins, the VCC, GND, and Signal. It can act as a switch if the circuit and the load circuit have different supply voltage. It is commonly used if the load circuit is AC. It is a switch used to connect isolated connection from the circuit using a circuit signal. It has red LED that turns on every time the coil is energized or the signal pin has a high input.
A Relay operating at 12V can be used via motor output pins configured to work on the 12V output.
You have to connect Coil A and Coil B pin to evive motor output pin 1. Then using motor functions in Arduino IDE or by the “control” option in the menu, you can control the relay directly.