What is a through-beam sensor?  Basically in this sensor, light passes to the receiving element and this element immediately produces an electrical output. This means the transmitter and receiver will be at different ends. The sensor will give a different output when there is an object in it; And the sensor will give a different output when there is no object in it. The output can be NO or NC, and PNP or NPN.

What is a Photoelectric Sensor? A photoelectric sensor basically emits light from a transmitter, which contains a light-emitting element. The receiver at the other end will detect this light beam. When this emitted light is intercepted by any object, the intensity of the beam of light received by the receiver changes. The intensity of the light is continuously processed and converted into an electrical output. As the intensity varies, the electric output varies. This electrical output is then fed to any circuit and indicates whether or not any object has passed between the lights. This is the concept of the photoelectric sensor.

What is a transducer? Basically a transducer is a device that converts energy/signal into another form. For example, force, torque, light, speed, position etc. Conversion of differences in similar physical quantities. And specific applications are in automation, control systems, and measuring to convert physical parameters such as pressure, temperature, level, flow or the like. Brightness etc., in an electrical signal or vice versa. The term transducer is used instead of the term sensor. Transducers are defined as elements that experience relative changes when subjected to some physical change.

What are the benefits of smart sensors? Advantages of smart sensors is  Improve process performance Minimize maintenance by predicting equipment failure Log data for historic records and regulatory compliance Notify of anomalies that affect process quality Self-Test, Self-Calibration and Self-Diagnosis Multi-sensing capabilities High accuracy Improve processing performance

What are the different types of smart sensors?  There are basically five main types of smart sensors used in industrial automation. And they are  Level sensors  Temperature sensors  Pressure sensors  Infrared sensors  Proximity sensors

How Smart Sensors Work? Basically, a smart sensor consists of 5 basic components which are the base sensor, power supply, microprocessor, memory and communication module. A base sensor is a common sensor responsible for detecting physical quantities. A power supply is to supply power to the computing resource and perhaps to the sensor base. A microprocessor is a computing component, which enables the sensor to perform some data calculations in order to measure quantities and take action based on these analyses. Memory is dedicated to storing measured values and calculated data, and also stores the software logic that controls how the sensor handles this data. The communication module is the one that transmits and receives data between sensors and external devices over the same network or the Internet. Essentially a raw base sensor used to provide sensing capability, it is designed to measure physical quantities and produce analog signals. These analog signals need to be processed befor...

What is Smart Sensor? Basically, a smart sensor is a device that can measure a physical quantity and give an output related to the measured value just like a normal sensor, but it also has the ability to analyze some data from this measured quantity using built-in computing resources and use this data to take some action to increase the efficiency of the automation process. Use it. And smart sensors can also provide more accurate measurements, thanks to built-in computing resources that filter out any signal noise and convert the measured signal into a usable digital form without the need for transducers like normal sensors. Smart sensors have built-in communication capabilities that enable them to transmit data over the Internet or similar networks and give them the ability to communicate with external devices, which is the main reason why smart sensors are such important components in the Internet of Things.

What is Normal Sensor? Basically a normal sensor is a device capable of sensing physical quantities like temperature, pressure, flow etc. and gives an output correlated to that quantity. And this output can either be an on/off signal, i.e., a switching signal, such as a proximity sensor, or it can be an analog representation of a continuously measured physical quantity, usually in the form of millivolts or some change in resistance value, such as thermocouples or pressure sensors. A common sensor by itself will not be sufficient to be able to use this measured value in an automation system. Instead, a transducer is introduced to enable converting these measured millivolts or resistance into a usable format such as 4 to 20 mA. Then you will need a computing capability like a PLC to use these measured values in some calculations and actions for automation processes.

Bimetallic Temperature Measuring Instruments or Bimetallic Thermometers Bimetallic devices take advantage of the metal's expansion when heated. In these devices, two metals are bonded together and mechanically connected to the pointer. A bimetallic device causes one side of the bimetallic strip to expand more than the other when heated. And when the pointer is properly formed, the temperature measurement is displayed. A bimetallic instrument is a device for measuring temperature. A bimetallic device is a mechanical thermometer that indicates temperature by mechanical displacement using a bimetallic strip. Bimetallic thermometers are simpler in design and less expensive. A bimetallic thermometer is a mechanical thermometer and does not require any kind of power source. Also bimetallic thermometers are cheap to install and easy to maintain. Bimetallic thermometers are basically used over a wide temperature range. A bimetallic thermometer does not give correct readings at low temperat...

Resistance Temperature Detector Resistance temperature detector is also known as RTD. An RTD is a temperature measuring device that measures temperature when a resistance changes. It is a device made of platinum. RTD works on temperature and resistance relationship and RTD is a passive device. RTD consist of insulated copper wires and resistive elements. The temperature sensing element of an RTD is a resistive element. RTD is commanly known as resistance thermometer and is a commaly used thermometer to measure temperature. Benefits of RTD is high accuricy and high temperature range. The RTD sensing element is metal and when electrical resistance changes with temperature. There are two types of RTDs one is a thin film element and the other is a wire wound element. Thin Film RTD A thin film RTD is made of platinum film. A platinum film is known as a thin layer of resistive material and is formed on a ceramic substrate. Platinum thin film RTD is also known as Pt-RTD. Platinum thin film RT...

Biosensors A biosensor is an analytical device that produces a signal proportional to the concentration of an analyte in a reaction, biological or chemical Measures substances and reactions. A biosensor combines a biological element with a physico-chemical detector. Biosensors typically consist of enzymes, antibodies, cells, nucleic acids, aptamers, semi-conducting materials, nanomaterials, and electronic systems that include processors, signal amplifiers, and displays. All types of biosensors typically produce minimal sample size because the biological detecting element is highly selective for the analyte. Physical and electrochemical changes occurring on the outside of the biosensor will generate a signal within the conducting polymer layer. Types Of Biosensors Electrochemical biosensors Optical biosensors Electronic biosensors Piezoelectric biosensors Gravimetric biosensors Pyroelectric biosensors Magnetic biosensors Biosensors Applications Common healthcare checking Metabolites Mea...

Types of Hygrometer Dry & wet bulb hygrometer. (Psychrometer) Hair hygrometer Sling psychrometer. Chilled mirror dew point hygrometer Dry & wet bulb hygrometer. (Psychrometer) When water or ice covers the bulb of a thermometer (wet-bulb), latent heat is removed from the surface of the bulb as the water evaporates, and the wet-bulb temperature becomes lower than the air (dry-bulb) temperature. At a lower humidity, water evaporates more actively, so that the wet-bulb temperature lowers sharply.  The aspirated psychrometer measures humidity by measuring the difference between the dry-bulb temperature and wet-bulb temperature. A psychrometer, or a wet and dry-bulb thermometer, consists of two calibrated thermometers, one that is dry and one that is kept moist with distilled water on a sock or wick. At temperatures above the freezing point of water, evaporation of water from the wick lowers the temperature, such that the wet-bulb thermometer will be at a lower temperature than t...

Dry & wet bulb hygrometer. (Psychrometer) When water or ice covers the bulb of a thermometer (wet-bulb), latent heat is removed from the surface of the bulb as the water evaporates, and the wet-bulb temperature becomes lower than the air (dry-bulb) temperature. At a lower humidity, water evaporates more actively, so that the wet-bulb temperature lowers sharply.  The aspirated psychrometer measures humidity by measuring the difference between the dry-bulb temperature and wet-bulb temperature. A psychrometer, or a wet and dry-bulb thermometer, consists of two calibrated thermometers, one that is dry and one that is kept moist with distilled water on a sock or wick. At temperatures above the freezing point of water, evaporation of water from the wick lowers the temperature, such that the wet-bulb thermometer will be at a lower temperature than that of the dry-bulb thermometer.  When the air temperature is below freezing, however, the wet-bulb must be covered with a thin coati...

Comfort Parameters For Human Being Five major human comfort parameters are decided for this research study, which influence the indoor human comfort the most. The five parameters are namely thermal comfort, visual comfort, air quality, acoustic, and lighting. Temperature  humidity   flow  pressure  clean air  co2 % Temperature Sensor  RTD Thermocouple  thermistor RTD RTD (Resistance Temperature Detector) is a sensor whose resistance changes as its temperature changes. The resistance increases as the temperature of the sensor increases. RTD works by using a basic principle; as the temperature of a metal increases, so does the resistance to the flow of electricity. An electrical current is passed through the sensor, the resistance element is used to measure the resistance of the current being passed through it. Thermocouple  Thermocouple are the most common sensor types used to measure temperatures. These are preferred over the others for measu...

Hair Hygrometer Hair hygrometer  Hair hygrometer are called membrane hygrometer when the sensing element is a membrane. Hair hygrometer is a type of absorption hygrometer and uses the mechanical humidity sensing technique. Hair hygrometer is a type of absorption hygrometer, Which works on the principle that, "Change in moisture content causes change in physical and chemical properties of certain materials", Such as, human hair, animal membrane, Wood, Paper etc.. As human hairs are used in this hygrometer, this type is called as hair hygrometer. Construction  Working of hair hygrometer depends upon the physical changes in human hair i.e. tendency to lengthen, when they absorb moisture and shorten, after losing moisture and getting dry. This absorption depends upon temperature and partial water vapor pressure in atmosphere. Due to this, extension or elongation of hairs is a function of relative humidity  fig shows an arrangement, where expansion and contraction of human hai...

Light Dependent Resistor Real-life example   Security System Controlled by An Electronic Eye This security system controlled by an electronic eye project is based on photo sensing arrangement. The proposed system uses a 14-stage ripple carry binary counter to sense the intensity of light using LDR. The o/p makes a relay and buzzer for the required action. This project is very useful to deter burglars from malls, banks and shops. This project or systems  uses a light dependent resistor. When light falls on the LDR sensor, then the resistance of the sensor decreases, which lead to activate an alarm to give an alert to the user. This project is suitable in the application of providing security system for different types of area or place  like lockers, cash boxes,  malls, shops. The circuit of this project is placed inside of the cash box in malls or inside of the lockers  in such a way that, when a burglar opens the cash box or locker and uses a torch light to sear...

  Light Dependent Resistor (LDR)  Working Principle of Light Dependent Resistor (LDR) Light Dependent Resistor work based off of the principle of photoconductivity. Photoconductivity is an optical phenomenon in which the material’s conductivity is increased when light is absorbed by the material. When light falls i.e. when the photons fall on the device, the electrons in the valence band of the semiconductor material are excited to the conduction band. These photons in the incident light should have energy greater than the bandgap of the semiconductor material to make the electrons jump from the valence band to the conduction band. Hence when light having enough energy strikes on the device, more and more electrons are excited to the conduction band which results in a large number of charge carriers. The result of this process is more and more current starts flowing through the device when the circuit is closed and hence it is said that the resistance of the device has been de...

Multiple Choice Questions and Answers on Sensors for IOT Multiple Choice Questions and Answers on Temperature Sensor 1. Which sensor is used for monitor electric distribution and switching equipment temperature? a) LM35 b) ESP8266 c) DHT11 d) RFM3200 Answer: RFM3200 2. Line of sight of wireless sensor tag is ________ a) 750ft b) 700ft c) 500ft d) 550ft Answer: 700ft 3. How many pins does temperature sensor have? a) 5 legs b) 2 legs c) 4 legs d) 3 legs Answer: 3 legs 4. Which of the following is the Wireless battery-free sensor? a) LM35 b) RFM3200 c) ESP8266 d) DHT11 Answer: RFM3200 5. Which sensor is linear and low accuracy? a) Thermistor b) Resistance Thermometer c) Thermocouple d) Semiconductor based sensor Answer: Semiconductor based sensor 6. What is ESP8266? a) WIFI module b) Sensor c) Board d) USB cable Answer: WIFI module 7. Electric motor protection has which sensor? a) Pressure sensor b) Touch sensor c) Temperature sensor d) Humidity sensor Answer: Temperature sensor 8. What i...

Sensors Definition of sensor   A sensor is a device that detects and responds to some type of input from the physical environment. The specific input could be light, heat, motion, moisture, pressure, or any one of a great number of other environmental phenomena.  A sensor is a device that detects and responds to some type of input from the physical environment. The specific input could be light, heat, motion, moisture, pressure, or any one of a great number of other environmental phenomena. The output is generally a signal that is converted to human-readable display at the sensor location or transmitted electronically over a network for reading or further processing.  What is a Sensor? There are numerous definitions as to what a sensor is but I would like to define a Sensor as an input device which provides an output (signal) with respect to a specific physical quantity (input). The term “input device” in the definition of a Sensor means that it is part of a bigger ...