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How to connect current sensor with nodemcu?

How to connect current sensor with nodemcu?
Sep30, 2024

Connecting a current sensor with a NodeMCU involves a few steps. Here’s a general overview:

1.  Choose a current sensor: There are many types of current sensors available, such as Hall effect sensors or shunt resistors. Select a sensor based on your requirements and available resources.
2. Identify the sensor pins: Look for the pinout diagram or datasheet of your selected current sensor and identify the pins for power supply, ground, and signal output.
3. Connect power supply and ground: Connect the power supply pin of the sensor to the 3.3V pin of the NodeMCU, and connect the ground pin of the sensor to the GND pin of the NodeMCU.
4. Connect signal output: Connect the signal output pin of the sensor to any available analog input pin of the NodeMCU, such as A0.
5. Code the NodeMCU: Write code to read the analog input from the current sensor and process the data. For example, you can use the analogRead() function to read the voltage at the analog input pin and convert it to current using the sensor’s sensitivity. Then, you can use the WiFi capabilities of the NodeMCU to send the data to a cloud service or to a local server.

Here’s an example code snippet that reads the voltage at pin A0 and converts it to current using a Hall effect sensor with a sensitivity of 100 mV/A:

Arduino Copy code

const int sensorPin = A0;
const float sensitivity = 0.1// 100 mV/A
void setup() {
Serial.begin(9600);
}
void loop() {
int sensorValue = analogRead(sensorPin);
float voltage = sensorValue * (3.3 / 1023); // convert ADC value to voltage
float current = voltage / sensitivity;
Serial.print(“Current (A): “);
Serial.println(current);
delay(1000);
}

Note: This is just an example code snippet and may need to be modified based on your specific requirements and sensor characteristics.