Meet Your Kit¶
Your Flowlence IoT Kit contains everything you need to build the four smart-city projects in this tutorial — no breadboard, no soldering, no extra parts to buy. Every sensor ships on a small breakout board with a 3-pin Dupont cable that plugs straight into the ESP32 Plus shield.
The ESP32 Plus: your city's brain¶
Every project in this tutorial revolves around the ESP32 Plus board. It's a standard ESP32 microcontroller mounted on a shield that exposes every pin as a labelled G / V / S (Ground / Voltage / Signal) header — which means you never need a breadboard. You plug the 3-pin cable from any sensor straight into the pin number the tutorial tells you to use.
Here's the same board with every region labelled — refer back to this whenever a tutorial mentions a part of the board you're not sure about:
What's on the board¶
| Region | What it's for |
|---|---|
| USB-C port (5 V) | Power + upload cable from your computer |
| External power jack (DC 7–12 V) | Power from a battery or adapter when not plugged into a computer |
| Reset button | Restart the program without re-uploading (the silkscreen misspells this as "Peset" — it's a manufacturing typo, the function is correct) |
| 14 digital ports (top row) | Digital input/output pins with G/V/S headers |
| 12 digital ports (middle row) | More digital pins, same layout |
| I²C communication interface (SCL / SDA) | For the LCD Display, RFID Reader, and other I²C devices |
| Analog port (3.3 V) | For analog sensors like the Soil Moisture Probe |
| Analog IN (io32, io34, io35, io39) | Input-only pins — good for sensors, can't be used as outputs |
| Serial communication interface (5 V) | Advanced — for talking to other devices over serial |
| Power rails (3V3, 5V, GND, VIN) | Handy access to power for projects that need extra hookups |
See the Pin Map & Shield Layout for the exact pin each sensor uses.
Why is the board called 'Plus'?
The plain ESP32 exposes its pins as two bare rows on the underside. The Plus variant adds the G/V/S headers, the DC power jack, and the full-size USB-C — so it's ready for beginners to use without a breadboard. The ESP32 chip itself is the same.
Sensors and modules in your kit¶
These are the components you'll use across the four projects, grouped by smart-city pillar.
🌿 Sustainability — for Smart Agriculture¶
| Component | What it does |
|---|---|
| Soil Moisture Probe | Measures how wet or dry the soil is |
| Water Level Detector | Measures depth of water in the tank |
| Water Pump | Submersible pump that moves water from the tank |
| Relay Module | Switches the high-power pump on/off under ESP32 control |
| Water Pipe + Plastic Box | The tubing and reservoir for the water |
| White LED module | Status indicator — used as the "low water" warning |
🚦 Mobility — for Smart Parking¶
| Component | What it does |
|---|---|
| Distance Sensor (Ultrasonic) | Measures how close an object is, using sound waves |
| Servo Motor | Rotates to a precise angle — used as the gate |
| RFID Reader | Reads the unique ID stored in cards and key-fobs |
| RFID Cards + Fob | The "tags" people scan to authenticate |
🚨 Protection — for Smart Safety¶
| Component | What it does |
|---|---|
| Fire Detector | Senses the infrared light produced by an open flame (the kit's "smoke sensor") |
| Gas Leak Sensor | Detects combustible gases like LPG and propane |
| Active Buzzer | Makes the loud alarm sound when triggered |
🌡️ Comfort — for Smart Temperature¶
| Component | What it does |
|---|---|
| Temperature & Humidity Sensor (DHT11) | Measures air temperature and humidity |
| DC Motor | Spins continuously — used as the cooling fan |
| LCD Display | Shows live temperature and humidity readings |
🔧 Supporting parts¶
| Item | Use |
|---|---|
| 3-pin Dupont cables | Connect each sensor module to the ESP32 Plus |
| USB-C cable | Power and program the ESP32 from your computer |
| AA Battery Holder | Optional — power the ESP32 standalone for portable demos |
Taking care of your kit¶
Before you plug anything in
- Always disconnect the USB cable before connecting or moving a sensor cable.
- The 3-pin Dupont cables have a keyed connector — they only fit one way. If it doesn't slide on easily, you're trying it backwards or offset by a pin.
- Components are reusable — handle them gently and return them to the kit between sessions.
Sensors that need extra care
- Water Pump — must be fully submerged before running, or it will burn out.
- Gas Leak Sensor — gets warm during use (there's a tiny heater inside), this is normal.
- Fire Detector — for testing use a small candle or long lighter with adult supervision; never test near flammable materials.