Electronic thermometer temperature measuring principle and application field

Life used in many electronic thermometer, used in both daily life and industrial machinery, electronic thermometer is an important equipment, but curious people will ask, what is electronic thermometer? It is used in what place? Instrument to answer: electronic thermometer with thermistor or thermocouple elements such as temperature components to implement the temperature sensor. Temperature sensor is not as two types: contact and non-contact. Tactile sensor is in direct contact with the object to be tested, thus to temperature measurement, this is the basic form of temperature measurement; Non-contact way is thermal radiation from the infrared measurement object, to measure the temperature of the object can be remote, can't do this is contact. Contact temperature sensor with thermocouple, heat resistance, etc. , to use its thermoelectric emfs or resistance with the temperature change of characteristics to measure the temperature of the object, usually with combination of bimetallic strip or magnetic relay switch control. Thermocouple is copper & ndash; Lala, nickel chromium & ndash; Nickel aluminum, platinum & ndash; Platinum rhodium appear on the bonding interface of different metals or alloys, such as temperature difference and produce thermoelectric emfs, measuring its thermoelectric emfs temperature sensor to measure object. Thermistor is a kind of such as semiconductor oxide ceramic as the resistance of the body, its resistance with the temperature change is very significant, thermal resistance has a positive temperature coefficient ( PTC(列车自动控制系统) And negative temperature coefficient ( NTC） A sharp change, and reaches a certain temperature resistance type critical CTR thermistor. Using a thermistor sensor resistance with the temperature change is the temperature resistance constitutes a bridge circuit of temperature measurement, which can eliminate temperature drift caused by temperature change, and can effective measurements of drift and noise. This sensor is simple, small, strong and simple in design, in addition to the widely used in household appliances such as microwave oven, electric blanket, cold, air conditioning, also widely used in automobiles, ships, control equipment, industrial measurement, etc. In some European countries to use very much, so to speak, this product is very sell like hot cakes products!