Difference and connection between transmitter and sensor

Sensors are devices that convert physical signals into electrical signals. In the past, we used to talk about physical signals. Now other signals are available.

A transmitter is an instrument that converts non-standard electrical signals into standard electrical signals.

Sensors and transmitters are the concepts of thermal instruments. Sensors convert non-electrical physical quantities such as temperature, pressure, liquid level, material and gas characteristics into electrical signals or send physical quantities such as pressure and liquid level directly to transmitters. The transmitter amplifies the weak electric signal collected by the sensor for transmitting or starting the control element, or converts the non-electric input of the sensor into the electric signal for amplifying at the same time for remote measurement and control. Analog quantities can be converted to digital quantities as required.

Sensors and transmitters together form an automatic monitoring signal source. Different physical quantities require different sensors and corresponding transmitters.

There is also a transmitter which does not convert physical quantities into electrical signals, such as a "differential pressure transmitter" of a boiler water level gauge. It transmits the condensate water from the lower part of the liquid level sensor and the upper part of the steam to the bellows of the transmitter through the instrumentation tube, and uses the differential pressure on both sides of the bellows to drive the mechanical amplifier with a pointer. A remote meter for water level. Of course, it is also possible to transform analog signals into digital quantities. The above is just a conceptual explanation of the difference between sensors and transmitters.

In other words, sensors are devices or devices that can be measured and converted into available output signals according to certain rules. They are usually composed of sensitive elements and conversion elements. When the output of the sensor is a prescribed standard signal, it is called a transmitter.