Introduction

In the previous session, we looked at several types of mechanical switches and grouped them based on the number of inputs and outputs. Mechanical switches, on the other hand, come in a variety of shapes and sizes depending on how mechanical energy is given to them. The majority of switches operate on the same concepts and have the same type of pins; however the push button has a somewhat different operation and structure. In this tutorial, we will investigate the operation of a push button and construct two-way switching circuits that are common in our homes.

Working of the Push Button

Push buttons are generally open tactile switches that allow us to power the load by pressing them. Simply said, when we press the button, the circuit is linked; when we release it, the circuit is disconnected. The best example of a push button application is the keys on our keyboard; as we press the button, the corresponding letter prints on screen constantly until we release the button. When the button is not pressed, the opposite pins are connected and the neighboring pins are not connected, as seen in the image below. When we press the button, we can see that the adjacent pins connect, allowing energy to pass through to the opposite side.


Simple push button circuit to control the LED.


Activity: - 6 – Push button-controlled LED  

            Create a circuit in Tinkercad using a push button switch to learn about the operation and use of push buttons in real time.

Components Required: -

1.      Battery 9V - 1

2.      LED - 2

3.      Resistor 470 Ohm – 2

4.      Push button Switch

Connection Procedure

  1. Using the above list, choose and place the appropriate components in the circuit area.
  2. Arrange the components in your circuit area as shown below.
  3. Connect the wire from the battery's positive terminal to the push button terminal 1B, then connect the wire from the button's 2B terminal to the resistor terminal 1.
  4. Connect the other end of the resistor to the anode of the led and the cathode of the led to the negative of the battery.
  5. Once we've finished connecting the circuits, launch the simulation and move your mouse over the push button to observe the led turn on.
  6. When we remove the pointer and release the click, the LED turns off.

Circuit Diagram: 


Two-way Switching Circuit

This section will go over the two-way switching circuit, which is often utilized in our homes and businesses. In the stairwell, we normally have two switches to control one light; similarly, in the bedroom, we have two switches, one near the entry and another near the bed, to control one light or fan.

Normally, SPDT switches with one INPUT and TWO output terminals are used for two-way switching applications. Two SPDT switches are used to control one LED in the circuit below. The positive terminal of the battery is linked to the S1 common terminal, and the S2 common terminal is connected to the anode of the LED. Terminal 1 of both switches is connected, and terminal 2 of both switches is connected in the same way. When both switches common - terminal 1 are connected, the light will turn on, and when both switches common - terminal 2 are linked, the LED will turn on. Here, we may utilize two switches to control one load, and we can position the switches as needed.

Activity: - 7 – Two way Switching Circuit  

            Create a two-way switching circuit with two SPDT switches to demonstrate the real-time use of two-way switching circuits seen in our home's staircases.

Components Required: -

1.      Battery 9V - 1

2.      LED - 1

3.      Resistor 470 Ohm – 1

4.      Slide Switch -2

Connection procedure:

  1. Select and arrange the components in the circuit area according to the given list.
  2. Turn the Slide switch so that it faces the terminals and connect both switches terminal1 together. Connect both switches terminal2 in the same manner.
  3. Connect a wire from the positive battery terminal to the switch 1 common terminal and the switch 2 common terminal to the LED's anode.
  4. Connect the LED's cathode to the negative terminal of the battery through the 470-ohm resistor.
  5. Once the connection is complete, start the simulation and alter the slide switch position.
  6. We can now see that when both switches are set to common and terminal 1 is connected, the LED turns on.
  7. Similarly, when both switches common and terminal 2 are connected, the LED turns on.
  8. We realize that in order to turn on the light, we must keep both switches in the same position.

Circuit Diagram: -