In our day-to-day life, we are habituated to implement different types of sensors frequently in our power systems such as electrical and electronics appliances, load control systems, home automation or industrial automation, and so on.
There are a few types of sensors such as temperature sensors, IR sensors, ultrasonic sensors, pressure sensors, proximity sensors, and touch sensors are frequently used in most electronics applications.
Temperature Sensor
IR Sensor
Ultrasonic Sensor
Touch Sensor
Proximity Sensors
Pressure Sensor
Level Sensors
Smoke and Gas Sensors
In this chapter we are going to use few sensors which are –
LDR Sensor
An LDR (Light Dependent Resistor) is a component that has a (variable) resistance that changes with the light intensity that falls upon it. This allows them to be used in light sensing circuits. Â
The working principle of an LDR is photoconductivity, which is nothing but an optical phenomenon. When the light is absorbed by the material then the conductivity of the material enhances.
Applications of LDR
Light-dependent resistors are simple and low-cost devices. These devices are used where there is a need to sense the presence and absence of light is necessary. These resistors are used as light sensors and the applications of LDR mainly include alarm clocks, street lights, light intensity meters, burglar alarm circuits.
IR Sensor
An infrared sensor is an electronic device, that emits in order to sense some aspects of the surroundings. An IR sensor can measure the heat of an object as well as detects the motion. These types of sensors measure only infrared radiation, rather than emitting it.
The working principle of an infrared sensor is similar to the object detection sensor.
IR Sensor Applications
The applications of the infrared sensors mainly include the following.
Meteorology
Climatology
Analysis of Water
Gas detectors
Testing of Anesthesiology
Exploration of Petroleum
Safety of Rail
There are few more sensors which we will be discussing further in this course.