Arduino project · Water and plants · Medium
Water Tank Level Bar
Sixteen LEDs show how full the tank is. A red LED warns when it is nearly empty.
What you will learn
- How level sensors are shown
- How to add a low-level warning
- How to scale one range to another
How it works
The level (0 to 100) is mapped to 0 to 16 LEDs. Below 20 percent the red LED lights.
Try this next
- Start a pump below 20 percent.
- Send an SMS when it is empty.
- Log the level every minute.
The simulator program and explanation on this page are original. The idea follows a classic Arduino project that students have built for years.
Parts: sensors and actuators (tap to show or hide)
Try the inputs (virtual sensors)
Pins (you can change them)
| Part | Arduino pin (change it here) | How to wire it |
|---|
Every wire, one by one
Red rail = 5 V from the Arduino 5V pin. Black rail = GND. The coloured wires carry signals. Match the wire colours on the drawing to this list.
| # | Colour | From (part and leg) | To |
|---|
Steps run from top to bottom, then start again. While the simulation runs, the active step is highlighted in green.
Quantities come from the parts you added. The store links open a search for that item on Robu.in, Amazon.in and ThinkRobotics, so you always see what is in stock today. Check the model, voltage and price before you order.
| # | Item | Qty | Search term | Buy / compare |
|---|
The PDF has the circuit sketch, pin table, every wire, sequence, full code, the parts list with store links, do’s and don’ts for each part, and the safety notes. The project file lets you come back and keep editing.
In the real world
A water tank
Move the water level slider. The water in the real tank rises and falls.
Tip: use the gold tab at the bottom of the circuit drawing to pull the real-world view up over the Arduino board. Your parts stay visible above it, so you can press a button and watch the real scene react.
- Water level sensor = how full the tank is
- LED = warning lamp