Counting the number of items moving on the conveyor belt using Lever type limit switch
with Arduino, Node MCU, ESP32
Limit switches explained: In this article, we’re going to introduce you to a device called a Limit Switch.
There’s probably not a day that goes by where you don’t use or encounter a limit switch at home, or at your workplace.
Types of limit switches
There are 4 general types of limit switches:
- Whisker
- Roller
- Lever
- Plunger
What are limit switches?
A limit switch is an electromechanical device operated by a physical force applied to it by an object.
Limit switches are used to detect the presence or absence of an object.
These switches were originally used to define the limit of travel of an object, and as a result, they were named Limit Switch
Limit switches are electromechanical devices consisting of an actuator mechanically linked to an electrical switch.
When an object contacts the actuator, the switch will operate causing an electrical connection to make or break.
Limit switches are available in several switch configurations: Normally Open, Normally Closed, or one of each.
Limit switches could be used to count passing objects, or determining the position of a hydraulic cylinder.
Generally speaking, limit switches are capable of handling much higher current values than proximity sensors.
Bump Sensor Limit switches crash, collision sensor interfaced with Arduino
Bump sensor has three pins of which one is connected to 5 volts DC, other to GND and third pin with 10 K connected through switch to ground as shown is connected to Pin 8 of Arduino. Whenever switch is pressed Pin 8 goes high. Now we need to have two LEDs and a buzzer to be connected to Arduino for signalling purposes. Green LED is connected to Pin 2 of Arduino which switches on whenever the Arduino is switched on. Red LED is connected to Pin 3 and buzzer connected to pin 4 goes high whenever Pin 8 goes high. In the Arduino, Node MCU, ESP32 a counter is set to count the number of times Pin 8 goes high. This directly the number of items moved on the conveyor belt.