A voltage sensor is a device that measures the electrical potential difference between two points in a circuit. It provides real-time voltage readings, which are essential for monitoring and controlling electrical systems. Voltage sensors are widely used in applications such as battery monitoring, power supply regulation, renewable energy systems, and industrial automation. They are particularly useful in scenarios where precise voltage measurement is critical for system performance and safety.
Below are the general technical specifications for a typical voltage sensor module (e.g., a voltage divider-based sensor like the commonly used 0-25V sensor module):
The following table describes the pinout of a standard voltage sensor module:
Pin Name | Description |
---|---|
VCC |
Power supply input (3.3V or 5V DC, depending on the microcontroller used). |
GND |
Ground connection. |
OUT |
Analog voltage output, proportional to the input voltage (scaled down). |
VIN+ |
Positive terminal for the voltage to be measured. |
VIN- |
Negative terminal for the voltage to be measured (usually connected to ground). |
VCC
pin to the 5V or 3.3V output of your microcontroller and the GND
pin to the ground.VIN+
and VIN-
pins. Ensure the input voltage does not exceed the sensor's maximum rating (e.g., 25V).OUT
pin to an analog input pin on your microcontroller. The output voltage will be proportional to the input voltage, scaled down by the sensor's internal voltage divider.Below is an example of how to use a voltage sensor with an Arduino UNO to measure a voltage and display the result on the Serial Monitor.
// Define the analog pin connected to the sensor's OUT pin
const int sensorPin = A0;
// Define the scaling factor (e.g., 5:1 for a 0-25V sensor)
const float scalingFactor = 5.0;
// Define the reference voltage of the Arduino (typically 5V)
const float referenceVoltage = 5.0;
void setup() {
// Initialize the Serial Monitor for debugging
Serial.begin(9600);
}
void loop() {
// Read the analog value from the sensor
int sensorValue = analogRead(sensorPin);
// Convert the analog value to a voltage
float voltage = (sensorValue * referenceVoltage / 1023.0) * scalingFactor;
// Print the measured voltage to the Serial Monitor
Serial.print("Measured Voltage: ");
Serial.print(voltage);
Serial.println(" V");
// Wait for a short period before the next reading
delay(1000);
}
No Output or Incorrect Readings:
VCC
, GND
, and OUT
pins are properly connected.Output Voltage Exceeds Expected Range:
Fluctuating or Noisy Readings:
Arduino Displays Incorrect Voltage:
Q: Can I use this sensor to measure AC voltage?
A: No, this sensor is designed for DC voltage only. Measuring AC voltage requires additional circuitry, such as a rectifier and filter.
Q: What happens if I reverse the VIN+
and VIN-
connections?
A: Reversing the connections may result in incorrect readings or damage to the sensor. Always connect the terminals as specified.
Q: Can I use this sensor with a 3.3V microcontroller?
A: Yes, most voltage sensors are compatible with 3.3V systems. However, ensure the output voltage does not exceed the microcontroller's ADC input range.
Q: How do I improve the accuracy of the sensor?
A: Calibrate the sensor using a known reference voltage and account for any offset or scaling errors in your calculations.