Why power matters for battery projects in Arduino - See It in Action

Why power matters for battery projects

📖 Scenario: You are building a small battery-powered Arduino project. You want to understand how power consumption affects battery life and how to measure it in your code.

🎯 Goal: Create a simple Arduino sketch that stores battery voltage readings, sets a power threshold, checks which readings are above the threshold, and prints those readings. This helps you see why power matters in battery projects.

📋 What You'll Learn

Create an array called batteryVoltages with these exact values: 4.2, 3.9, 3.7, 3.5, 3.3

Create a variable called powerThreshold and set it to 3.6

Create a new array called highPowerReadings that contains only the voltages from batteryVoltages that are greater than powerThreshold

Print each voltage in highPowerReadings on its own line

💡 Why This Matters

🌍 Real World

Battery-powered devices need to monitor their power levels to avoid sudden shutdowns and to optimize battery life.

💼 Career

Understanding power management and battery monitoring is important for embedded systems engineers and IoT developers.

1

DATA SETUP: Create battery voltage readings

Create an array called batteryVoltages with these exact values: 4.2, 3.9, 3.7, 3.5, 3.3

Arduino

// Create an array called batteryVoltages with the values 4.2, 3.9, 3.7, 3.5, 3.3
// Your code here

Need a hint?

Use float batteryVoltages[] = {4.2, 3.9, 3.7, 3.5, 3.3}; to create the array.

2

CONFIGURATION: Set power threshold

Create a variable called powerThreshold and set it to 3.6

Arduino

float batteryVoltages[] = {4.2, 3.9, 3.7, 3.5, 3.3};
// Create a float variable powerThreshold and set it to 3.6
// Your code here

Need a hint?

Use float powerThreshold = 3.6; to set the threshold.

3

CORE LOGIC: Filter voltages above threshold

Create a new array called highPowerReadings that contains only the voltages from batteryVoltages that are greater than powerThreshold. Use a for loop with index i and a counter count to store the results.

Arduino

float batteryVoltages[] = {4.2, 3.9, 3.7, 3.5, 3.3};
float powerThreshold = 3.6;
// Create an array highPowerReadings and fill it with voltages > powerThreshold
// Your code here

Need a hint?

Use a for loop and an if statement to check each voltage and add it to highPowerReadings.

4

OUTPUT: Print voltages above threshold

Use a for loop with index j from 0 to count - 1 to print each voltage in highPowerReadings on its own line using Serial.println(). Also add Serial.begin(9600); in setup().

Arduino

float batteryVoltages[] = {4.2, 3.9, 3.7, 3.5, 3.3};
float powerThreshold = 3.6;
float highPowerReadings[5];
int count = 0;
for (int i = 0; i  powerThreshold) {
    highPowerReadings[count] = batteryVoltages[i];
    count++;
  }
}

void setup() {
  Serial.begin(9600);
  // Print voltages above threshold
  // Your code here
}

void loop() {
}

Need a hint?

Use Serial.println(highPowerReadings[j]); inside a for loop in setup().