Temperature is the main concern for most process industries. The main property of temperature is that the increase or decrease of temperature will affect the movement energy of particles in the part. Generally, a sensor or transducer is a physical device that can convert a type of process variable into a desired signal type. The article will briefly explain what are the temperature sensors.
Temperature is one of the more commonly measured quantities of equipment or its surrounding conditions, especially for electronic components. This is because electronic devices and circuits generate heat and require some type of thermal management. There are many types of temperature sensors suitable for such applications and provide different functions or specifications. For example, a temperature sensor can provide an analog or digital output. The following are some very common types of temperature sensors: negative temperature coefficient thermistors, resistance temperature detectors, thermocouple sensors, semiconductor sensors, infrared sensors, etc.
The cost of the temperature sensor depends on the type of work it is suitable for. However, the measurement accuracy of the temperature sensor will determine its price. Therefore, the cost depends on the accuracy of the temperature sensor. Current temperature sensors are designed to reduce cost and efficiency.
Thermistor sensor: It is an abbreviation for negative temperature coefficient thermistor. It is a special type of resistor whose resistance changes according to temperature. The output of the thermistor is nonlinear due to its exponential nature; but it can be linearized according to its application. The effective operating range of the thermistor sensor is from -50 to 250 ° for glass-encapsulated thermistors or 150 ° for standard thermistors.
Resistance temperature detector: Resistance temperature detector is one of the sensors that measure very accurately. In a resistance temperature detector, the resistance is proportional to the temperature. The sensor is made of platinum, nickel and copper metals. It has a wide range of temperature measurement functions and can be used to measure the temperature in the range of -270oC to +850oC. An RTD needs an external current source to work properly. To use an RTD to measure temperature, it must be connected to a Wheatstone bridge and a constant current source. Measure the voltage output to determine the resistance. Then, the temperature can be derived from the linear resistance-temperature relationship of a given RTD.
Thermocouple sensors are very common contact temperature sensors. They are compact, inexpensive, simple to use, and can quickly respond to temperature changes. It consists of a sensing element, which can be glass or epoxy coated, and has 2 wires so they can be connected to the circuit. They measure temperature by measuring changes in current resistance. The thermistor has two forms, NTC or PTC, and usually has a lower cost.
Semiconductor sensor: A semiconductor sensor is a device that appears in the form of IC. Generally, these sensors are called IC temperature sensors. Current output temperature sensor, resistor output temperature sensor, resistor output silicon temperature sensor, diode temperature sensor, digital output temperature sensor. Current semiconductor temperature sensors provide high linearity and high accuracy in an operating range of approximately 55°C to +150°C.
The infrared sensor is an electronic instrument, and the infrared sensor is a non-contact temperature sensor. They are photosensitive devices that can detect infrared (IR) radiation from surrounding areas or objects to measure heat. These sensors are divided into thermal infrared sensors and quantum infrared sensors.
The article mainly introduces what are the temperature measurement sensors. You can learn that there are many types of temperature sensors suitable for temperature measurement applications and provide different functions or specifications by browsing the full text. For example, a temperature sensor can provide an analog or digital output. The following are some very common types of temperature sensors: negative temperature coefficient thermistors, resistance temperature detectors, thermocouple sensors, semiconductor sensors, infrared sensors, etc.
