How do I use a relay with Arduino Uno?
Just start by defining the digital pin number 2 of the Arduino as the Relay pin. Then define the pinMode as OUTPUT in the setup section of the code. Finally, in the loop section we are going to turn on and off the relay after every 500 CPU cycles by setting the Relay pin to HIGH and LOW respectively.
What is relay Arduino Uno?
A relay is an electrically operated switch that can be turned on or off, letting the current go through or not, and can be controlled with low voltages, like the 5V provided by the Arduino pins. Controlling a relay module with the Arduino is as simple as controlling any other output as we’ll see later on.
Can an Arduino power a relay?
Instead, you use a low-voltage control signal from the Arduino to control a relay, which is capable of handling and switching high-voltage or high-power circuits. A relay consists of an electromagnet that, when energized, causes a switch to close or open.
How many relays can an Arduino Uno control?
Each IO Expander can control up to 16 daisy chained Relay Expanders for a total of 256 relays. Then connecting 255 IO Expanders together you can selectively control up to 65,280 relays.
How do I connect 4 relay modules to Arduino?
Control 4-Channel Relay Module
- Bill of materials. Arduino board with USB cable (we use Arduino Uno)
- Connect wires on relay module. Connect six female pins of wires with relay module male pins as shown on the picture.
- Connect wires with Arduino.
- Open Arduino IDE and write code.
- Upload code to Arduino.
What is relay Arduino?
A relay is a programmable electrical switch, which can be controlled by Arduino or any micro-controller. It is used to programmatically control on/off the devices, which use the high voltage and/or high current. It is a bridge between Arduino and high voltage devices.
How much current does a 12V relay draw?
150-200 mA
Current rating The current draw of the coil is not normally shown but is typically 150-200 mA with a corresponding coil resistance of around 80-60 W.