What is the difference between a pressure sensor and a pressure transmitter?

Nowadays, most of the sensors that people often say are actually composed of two parts, namely: the sensitive element and the conversion element, where the sensitive element refers to the part of the sensor that can directly feel or respond to the measurement;

The conversion element refers to the part of the sensor that the sensitive element feels or responds to be measured and converted into the electrical signal that is suitable for transmission or measurement, with the development of integrated technology, people also install this part of the circuit and the power supply circuit together inside the sensor, so that the sensor can output, and is convenient for processing the available signal of transmission, and when the previous technology is relatively backward, the so-called sensor refers to the sensitive element above, and the transmitter is the conversion element in the above. <>

Pressure sensors have naturally become commonly used sensors in industrial practice, and are widely used in various industrial automatic control environments, involving water conservancy and hydropower, railway transportation, intelligent buildings, production automatic control, aerospace, military petrochemical, oil wells, electric power, ships, machine tools, pipelines and many other industries.

While talking about pressure sensors, Bu Gong of Famet Pressure Sensor Division will take you to understand the concept of pressure transmitters.

A pressure sensor usually refers to a sensitive element that converts a changing pressure signal into a corresponding change in resistance signal or capacitive signal, such as piezoresistive elements and piezoelectric capacitive elements.

Typically, a sensor consists of two parts: a sensing element and a conversion element. Among them, the sensitive element refers to the part of the sensor that can directly sense or respond to the measured object; A conversion element is a part of a sensor that converts the measured strain perceived or responded to by a sensitive element into an electrical signal suitable for transmission or measurement.

A pressure transmitter generally refers to a complete set of circuit units that measure pressure consisting of a varistor element and a regulating circuit. Generally speaking, it can directly output a standard voltage signal or a current signal, which has a linear relationship with the pressure, and can be directly collected by instruments, PLCs, acquisition cards and other equipment.

Since the output signal of the sensor is generally weak, modulation and amplification are required. With the development of integrated technology, people also put this part of the circuit into the sensor along with the power supply circuit. In this way, the sensor can output a useful signal that is easy to process and transmit.

In the past, when the technology was relatively backward, the so-called sensor refers to the sensitive element in the above article, and the transmitter is the conversion element in the above article.

Pressure switch: When the pressure in the system is higher or lower than the rated safety pressure, the disc in the sensor moves instantaneously, and the switch joint is pushed on or off by connecting the guide rod, when the pressure drops to or rises to the rated recovery value, the disc instantly resets, and the switch automatically resets, or simply put, when the measured pressure exceeds the rated value, the free end of the elastic element produces displacement, directly or after comparison, the switch element is pushed to change the on-off state of the switch element, so as to achieve the purpose of controlling the measured pressure. The elastic elements used in pressure switches include single-turn spring tubes, diaphragms, diaphragm boxes and bellows.

Pressure transmitter: When the pressure signal acts on the sensor, the pressure sensor converts the pressure signal into an electrical signal, which is amplified by differential amplification and output amplifier, and finally converted into a standard current output signal of 4-20mA that corresponds linearly to the liquid level pressure of the measured medium (liquid) through the voltage and current. Main technical parameters Power supply:

24VDC Output 4 20mA 2-wire Zero Adjustable Range: 5% Range Adjustment Ratio: 3:

1 or more Measuring range: -100kpa 0 60mpa Load characteristics: The load is within 0 600 (24VDC power supply) to maintain constant current output Flameproof type D II BT4, intrinsically safe type IA II CT5 Overvoltage limit:

2 times the upper pressure Temperature range: Process: -20 60 Accuracy class:

Stability: Weight: about 1kg Characteristic analysis.

The sensor is part of the transmitter and the transmitter unit is missing.

Sensors with a standard output signal are often referred to as transmitters.

The so-called standard signal refers to the signal whose form, size, and load capacity meet the requirements of a specific specification. Among them, the most used are 4 20mA DC constant current electricity, 1 5V DC regulated voltage electricity, and 20 100kPa compressed air.

First, the principle is different.

1. The pressure sensor resistance strain gauge is one of the main components of the piezoresistive strain sensor. The working principle of metal resistance strain gauge is the phenomenon that the resistance value changes with mechanical deformation due to the strain resistance adsorbed on the base material, which is commonly known as the resistance strain effect.

2. The ceramic pressure sensor is based on the piezoresistive effect, the pressure directly acts on the front surface of the ceramic diaphragm, so that the diaphragm produces a slight deformation, and the thick film resistance is printed on the back of the ceramic diaphragm and connected into a Wheatstone bridge, due to the piezoresistive effect of the varistor, the bridge produces a voltage signal that is highly linear proportional to the pressure and proportional to the excitation voltage.

3. The working principle of the diffusion silicon pressure sensor is also based on the piezoresistive effect, using the principle of piezoresistive effect, the pressure of the measured medium directly acts on the diaphragm of the sensor (stainless steel or ceramic), so that the diaphragm produces a micro displacement proportional to the pressure of the medium, so that the resistance value of the sensor changes, the electronic circuit is used to detect this change, and the output of a standard measurement signal corresponding to this pressure is converted.

4. The electrical components of the pressure transmitter to feel the pressure are generally resistance strain gauges, which are sensitive devices that convert the pressure on the test piece into an electrical signal. There are two most widely used types of electrical strain gauges: metal resistance strain gauges and semiconductor strain gauges. There are two types of metal resistance strain gauges: wire strain gauges and metal foil strain gauges.

5. The strain gauge is usually tightly bonded to the mechanical strain matrix through a special adhesive, and when the stress changes under the force of the matrix, the resistance strain gauge also produces deformation together, so that the resistance value of the strain gauge changes, so that the voltage applied to the resistance changes.

Second, the related applications are different.

1. Pressure sensors are mainly used in: booster cylinders, boosters, gas-liquid booster cylinders, gas-liquid boosters, presses, compressors, air conditioning and refrigeration equipment and other fields.

2. Pressure transmitter:

1) Intelligent: Due to the emergence of integration, some microprocessors can be added to the integrated circuit, so that the transmitter has the functions of automatic compensation, communication, self-diagnosis, logic judgment and so on.

2) Integration: Pressure transmitters have been increasingly integrated with other measurement transmitters to form a measurement and control system. Integrated systems increase the speed and efficiency of operations in process control and factory automation.

3) Miniaturization: The market demand for small pressure transmitters is increasing, this small transmitter can work in extremely harsh environments, and only requires little care and maintenance, and has little impact on the surrounding environment, and can be placed in various important organs of the human body to collect data, without affecting the normal life of people.

The sensor is composed of two parts, namely the sensing element and the conversion element. The sensitive element refers to the part of the sensor that can directly sense or respond to the measurement; The conversion element refers to the part of the sensor that converts the measured perception or response of the sensitive element into an electrical signal suitable for transmission or measurement. Since the output signal of the sensor is generally weak, it needs to be modulated and amplified.

With the development of integrated technology, this part of the circuit and the power supply circuit are also installed inside the sensor. In this way, the sensor can output a usable signal that is convenient for processing the transmission.

The sensor is the sensor element described above, and the transmitter is the conversion element described above.

Generally speaking, the pressure transmitter is used to measure the pressure value of gas or liquid (in mpa, etc.), and display the measured value on the screen for human-computer interaction, and can output a standard analog signal of 4-20mA;

The pressure sensor can be understood as two products: one is the force measurement value, the unit is N or KN, etc.; One is also the pressure measurement, which is measured in megapascals, etc.

The relationship between the two pressure transmitters can be understood as follows: the values measured by the pressure sensor have been collected, processed and transmitted through the circuit.

A pressure transmitter is an instrument device that converts pressure into an electric signal, and the standard signal output is generally a direct current signal such as 4 20mA or 1 5V. Pressure, differential pressure, absolute pressure and negative pressure can be measured.

When choosing the right pressure transmitter, an understanding of temperature is crucial.

If the measurement technology does not ensure a certain level of temperature compensation, there is a risk of serious errors, so temperature compensation is the key to ensuring accuracy. Therefore, when selecting a product, it is important to understand the temperature range required by the end user for their specific application. There are two factors to consider here:

Medium temperature and ambient temperature.

The medium temperature is the temperature to which the pressure hole is exposed.

Ambient temperature refers to the ambient temperature that surrounds the application and ultimately affects the electrical connections. The two values are different, and each will produce different results.

Pressure transmitters typically use temperature compensation to optimize the standard temperature range.

A pressure transducer is a device or device that can sense the pressure signal and convert the pressure signal into a usable output electrical signal according to a certain law.

A pressure sensor usually consists of a pressure-sensitive element and a signal processing unit. According to different types of test pressure, pressure sensors can be divided into gauge pressure sensors, differential pressure sensors and absolute pressure sensors.

Pressure sensor is the most commonly used sensor in industrial practice, which is widely used in various industrial automatic control environments, involving water conservancy and hydropower, railway transportation, intelligent buildings, production automation, aerospace, military industry, petrochemical, oil wells, electric power, ships, machine tools, pipelines and many other industries.

Summary. Dear, I am happy to answer that the principles of pressure sensors and differential pressure transmitters are similar, but not identical. A pressure sensor is a device that converts external pressure into an electrical signal output.

It usually consists of elastic elements, sensitive elements, sensor chips, etc. When external pressure is applied to an elastic element, it deforms it, causing the sensitive element to be displaced or deformed, which is finally converted into an electrical signal output by the sensor chip. A differential pressure transmitter, on the other hand, is a device that measures the pressure difference between two locations.

It typically consists of two pressure sensors, a differential amplifier, and other auxiliary circuitry. In a differential pressure transmitter, two pressure sensors measure the pressure at two positions separately, then calculate the pressure difference between them by means of a differential amplifier and convert the result into a standard signal output. So, while the principles of pressure sensors and differential pressure transmitters are similar, they are slightly different in terms of application and how they work.

Is the principle of the pressure sensor and the differential pressure transmitter the same, dear, I am happy to answer for you that the principle of the pressure sensor buried letter wheel and the differential pressure transmitter are similar, but they are not exactly the same. A pressure sensor is a device that converts external pressure into an electrical signal output. It usually consists of elastic elements, sensitive elements, sensor chips, etc.

When the pressure of the outer bend signal is applied to the elastic element, it will deform it, which will cause the sensitive element to be displaced or deformed, and finally converted into an electrical signal output through the sensor chip. A differential pressure transmitter, on the other hand, is a device that measures the pressure difference between two locations. Tennac typically consists of two pressure sensors, a differential amplifier, and other auxiliary circuitry.

In a differential pressure transmitter, two pressure sensors measure the pressure at two positions separately, then calculate the pressure difference between them by means of a differential amplifier and convert the result into a standard signal output. So, while the principles of pressure sensors and differential pressure transmitters are similar, they are slightly different in terms of application and how they work. 

What are the working scenarios? Different.

Dear, I am glad to answer that pressure sensors and differential pressure variable side feeders are both sensors that measure pressure, but their working scenarios are different. Pressure sensors are generally used to measure the static pressure of liquids or gases, such as tank water level, cylinder pressure, etc. It works by sensing the pressure exerted by the medium to be measured and converting the pressure into an electrical signal output.

The differential pressure transmitter is used to measure the pressure difference between two locations, such as the flow difference in the pipeline, the pressure difference between the inlet and outlet of the fan, etc. It works by converting the pressure difference between the two positions of the measured medium into an electrical signal output. Therefore, pressure sensors and differential pressure transmitters work in different scenarios, and it is necessary to select the right sensor according to the specific measurement needs. 

The principle of a pressure sensor and a differential pressure transmitter is not exactly the same, but they are both sensors used to measure pressure. A pressure sensor is a type of sensor that converts pressure into an electrical signal output. It usually consists of an elastic element and a bridge.

When subjected to pressure, the elastic element deforms, causing a change in the resistance of the bridge, resulting in an electrical signal output. The output signal of a pressure sensor is usually an analog signal that needs to be amplified and filtered before it can be used. A differential pressure transmitter is a sensor that converts differential pressure into an electrical signal output.

It usually consists of two pressure sensors and a differential amplifier. The two pressure sensors measure the pressure of the two positions of the hall sail respectively, and the differential amplifier subtracts the two signals to obtain the differential pressure signal output. The output signal of a differential pressure transmitter is usually an analog signal, which needs to be amplified and filtered before it can be used.

Therefore, while both pressure sensors and differential pressure transmitters are sensors used to measure pressure, they differ in principle and structure.