First, let's look at the origin of sensors: in order to get information from the outside world, people have to use sensory organs. However, it is far from enough to rely solely on people's own sense organs in the study of natural phenomena and laws as well as their functions in production activities. To accommodate this, sensors are needed. Therefore, it can be said that the sensor is the extension of human facial features, also known as electrical features.
As technology evolves, sensors become more widely used, with principles and structures ranging from simple to intelligent. Sensors have already penetrated into such extensive fields as industrial production, space exploration, ocean exploration, environmental protection, resource investigation, medical diagnosis, biological engineering, and even the protection of cultural relics.
So when did transmitters come into being? What does it have to do with sensors? How to see the difference between the sensor and the transmitter?
(1) As we know, a sensor is a general term for a device or device that can be measured and converted into a usable output signal according to a certain law. It is usually composed of a sensitive element and a conversion element. When the output of the sensor is a specified standard signal, it is called a transmitter.
(2), the concept of the transmitter is to convert non-standard electrical signals into standard electrical signals of the instrument, the sensor is the physical signal into electrical signals of the device, often used to speak of physical signals, now other signals also have (divided into two categories of physical sensors and chemical sensors). Primary instrument refers to the field measurement instrument or base control table, secondary instrument refers to the use of primary meter signal to complete other functions, such as control, display and other functions of the instrument.
(3), the sensor is the non-electrical physical quantity such as temperature, pressure, liquid level, material, gas characteristics into electrical signals or the physical quantity such as pressure, liquid level and other direct transmission to the transmitter. The transmitter amplifies the weak electrical signal picked up by the sensor for transmission or activation of the control element. Or a signal source that converts the non-electric quantity input by the sensor into electrical signals and amplifies them at the same time for remote measurement and control. The analog quantity can also be transformed into digital quantity according to the need. Sensors and transmitters together constitute automatic control of the monitoring signal source. Different physical quantities require different sensors and corresponding transmitters.
Still have a kind of transducer not the physical quantities into electrical signals, such as a boiler water level gauge of the differential pressure transmitter, it is the lower part of the water in the liquid level sensor and the upper part of the steam condensate to transmitter bellows tube instrument on both sides, with the differential drive on either side of the bellows mechanical amplification device using pointer indicates the a level meter far away. Of course, there are electrical analog quantity into digital quantity can also be called the transmitter. The above is just a conceptual illustration of the difference between a sensor and a transmitter.
Sensors and transmitters are originally the concept of thermal instruments. Just the principle and application needs are not the same, become somewhat different. The above is a comprehensive analysis of the transmitter and the sensor what the difference is.
