Introduction
In this tutorial, we will learn about the KY-017 module, what is a mercury switch and we will build a simple project to detect if the KY-017 module is tilted using an Arduino.
Mercury Open Optical Module KY-017
The KY-017 Module will be our main component for this tutorial. This module has a mercury switch and mounted on a breakout board with an LED and resistor. Figure 1 shows the module as seen in fritzing.
Pinout
The KY-017 module has three pins.
| Component Pin | Description |
|---|---|
| (-) | GND |
| middle | +5V |
| S | Signal |
What is a Mercury Switch?
A mercury switch has a mercury blob as a means to close its internal contacts. If the switch is level, the mercury bridges the 2 contact points. But if the switch is tilted, the mercury moves on one side and the contact points are open.
Project - Arduino Tilt Indicator
After learning about the KY-017 module and the mercury switch, it is now time to build a project using the module. Our project will be a visual indicator when the KY-017 module is tilted.
Components
For this project, we need the following components:
- Arduino Uno board (1 pc.)
- KY-017 Mercury Open Optical Module (1 pc.)
- Jumper wires
Wiring Diagram
Figure 2 shows the connection between the Arduino Uno and the KY-017 Mercury Open Optical Module.
The KY-017 module pins are connected to the Arduino Uno board as follows:
| Component Pin | Arduino Uno board Pin |
|---|---|
| (-) | GND |
| middle | +5V |
| S | 8 |
The Code
Below is the Arduino sketch for our project. I have added comments to explain important parts of the code. Save the code as KY-017.ino and upload it to your Arduino board.
// Arduino and KY-017 module
void setup() {
pinMode(8, INPUT); // module is connected to pin 8
pinMode(13, OUTPUT); // built-in LED
}
void loop() {
if (digitalRead(8) == HIGH) { // if module is tilted, pin 8's state is HIGH
digitalWrite(13, HIGH); // switch On LED
}
else {
digitalWrite(13, LOW); // switch On LED
}
}
Project Test
Apply power to your Arduino Uno board. The Arduino’s built-in LED will light up when KY-017 is tilted.
