The types and characteristics of the transmitter and the role of the transmitter

The function of the transmitter is to detect the process parameters and transmit the measured values in the form of specific signals for display and adjustment.

The function in the automatic detection and adjustment system is to convert various process parameters such as temperature, pressure, flow, liquid level, composition and other physical quantities into a unified standard signal, and then transmit it to the regulator and indication recorder for adjustment, indication and recording.

Depending on the energy used, there are two types of transmitters: pneumatic transmitters and electric transmitters

1. Pneumatic transmitter.

The pneumatic transmitter uses dry and clean compressed air as the energy source, and it can convert various measured parameters into a barometric pressure signal of 0 02, so as to transmit it to the combined instrument of the unit such as regulation and display for indication, recording or adjustment.

The structure of the pneumatic transmitter is relatively simple, the work is more reliable, the anti-interference ability to electromagnetic field, radiation and temperature, humidity and other environmental influences is strong, and it can be fireproof and explosion-proof, and it is also relatively cheap; The disadvantages are that the response speed is slower, the transmission distance is limited, and it is more difficult to connect with the computer.

2. Electric transmitter.

The electric transmitter uses electricity as the energy source, and the connection between signals is relatively convenient, which is suitable for long-distance transmission and easy to connect with electronic computers. In recent years, it can also be explosion-proof for safe use. The disadvantage is that the investment is generally higher and is more affected by the interference of temperature, humidity, electromagnetic fields and radiation.

Attention should be paid to differential pressure transmitters when using:

1. When measuring gas pressure, the pressure port should be opened at the top of the process pipeline, and the transmitter should also be installed in the upper part of the process pipeline, so that the accumulated liquid can be easily injected into the process pipeline.

2. The impulse pipe should be installed in a place with small temperature fluctuations.

3. Prevent the transmitter from coming into contact with corrosive or overheated media.

4. Prevent the debris from being deposited in the catheter.

5. When measuring liquid pressure, the pressure port should be opened on the side of the process pipeline to avoid sedimentation and slag.

6. When measuring steam or other high-temperature media, it is necessary to connect a condenser such as a buffer tube, and the working temperature of the transmitter should not exceed the limit.

7. In the event of freezing in winter, anti-freezing measures must be taken according to the transmitter installed outdoors to avoid the expansion of the liquid in the impulse port due to icing, resulting in damage to the sensor.

8. When measuring liquid pressure, the installation position of the transmitter should avoid the impact of the liquid, so as to avoid damage to the sensor by overpressure.

9. When wiring, pass the cable through the waterproof joint or winding pipe and tighten the sealing nut to prevent rainwater from leaking into the transmitter housing through the cable. There are flammable and explosive gases, dusts, etc. in many production occasions in the petrochemical industry, and if the field instruments installed in this occasion produce sparks, they are easy to cause combustion or damage, resulting in huge losses of personnel and property.

Therefore, the instrument must have a safe spark and explosion-proof performance. Explosion-proof instruments have explosion-proof inspection certificate number and nameplate with explosion-proof type, grade and other marks.

Here's what it does:

1. Input overload protection;

2. Output over-current limit protection;

3. Long-term short-circuit protection of output current;

4. Two-wire port transient induction lightning and surge current TVS suppression protection;

5. Overvoltage limit protection of working power supply: 35V;

6. Reverse connection protection of working power supply.

A transmitter is a converter that converts the output signal of a sensor into a signal that can be recognized by a controller (or a signal source that converts the non-electric input of the sensor into an electrical signal and amplifies it for remote measurement and control).

What is the purpose of a transmitter? What is the role of a monocrystalline silicon pressure transmitter?

The purpose of the transmitter is simply to detect the process parameters and transmit the measured values in the form of specific signals for display and adjustment.

The temperature and humidity transmitter is a temperature and humidity integrated probe as a temperature measurement element, the temperature and humidity signals are collected, and after being processed by voltage stabilization filtering, operation amplification and other circuits, they are converted into current signals or voltage signal outputs with a linear relationship with temperature and humidity, and can also be directly connected to the 485 interface through the main control chip.

Sensors that are used in industrial fields and can output standard signals are called transmitters. This term is sometimes used interchangeably with sensors.

In the Principles of Automatic Control, a transmitter is a converter that converts the output signal of a sensor into a signal that can be recognized by the controller. As for the fact that it is sometimes common with sensors, the output signal of most modern sensors is already a signal that can be received by a universal controller, and this signal can be directly recognized by the controller without being converted by the transmitter. So, the traditional meaning of "transmitter" should be:

An instrument that converts the output signal of a sensor into a standard signal that can be accepted by a controller or measuring instrument." In automation: signal source - > sensor - > transmitter - >-combinator controller - > actuator - > control output.

There are many types of transmitters, generally speaking, the transmitter sends a signal to the secondary instrument to make the secondary instrument display the measurement data.

A device that converts a physical measurement signal or an ordinary electrical signal into a standard electrical signal output or a communication protocol. Generally, it is divided into: temperature and humidity transmitters, pressure transmitters, differential pressure transmitters, liquid level transmitters, current transmitters, power transmitters, flow transmitters, weight transmitters, etc.

The current transmitter can directly convert the AC current of the main circuit of the test or the DC current of Wu Lupai into a DC4 20mA (DC1 5V through 250 resistance or DC2 10V through 500 resistance) constant current loop standard signal output in a linear proportional manner, and continuously transmit it to the receiving device.

A power transmitter is a measuring instrument that converts the measured amount of electricity (AC voltage, current, active power, reactive power, active energy, reactive energy, frequency, phase, power factor, DC voltage, current, etc.) into a linear proportional DC current cavity or voltage output (electric energy pulse output).

How Extended Data Composes:

The transmitter works on the principle of negative feedback, which is mainly composed of a measurement part, an amplifier and a feedback part.

The measurement part is used to detect the measured variable x and convert it into an input signal zi (voltage, current, displacement, force or torque) that can be accepted by the amplifier. The feedback part converts the output signal Y of the transmitter into the feedback signal Zf, and then sends it back to the input terminal.

The difference between ZI and the zeroed ZO signal ZO and the same feedback signal ZF is fed into the amplifier for amplification and converted into the standard output signal Y. (Photo by Du Shifan, Pacific Automobile Network).

Famet to help you answer: the intelligent pressure transmitter is an intelligent transmitter connected by the sensor and the microprocessor, which makes full use of the microprocessor's computing and storage capabilities, including data filtering, adjustment and other functions, the microprocessor is the core of the intelligent transmitter, which can not only calculate, store and process the measured data, but also adjust the sensor through the reaction circuit to achieve data collection.

The intelligent pressure transmitter is a commonly used transmitter. It is widely used in many fields, mainly for the measurement and control of weakly corrosive liquid lead, gas and vapor in industrial pipelines. So what are the characteristics of a smart pressure transmitter?

1.High-precision and reliable imported pressure chips.

2.Wide temperature compensation.

3.Compensation plate glue potting moisture-proof protection.

4.The full 316L diaphragm is more corrosion-resistant.

5.Micro amplifier, voltage, current, frequency signal output.

6.High-precision, all-stainless steel construction, after many stainless steel welds, to achieve an all-solid-state design, can be used for a long time in harsh explosion-proof place environments.

7.High-quality terminal blocks, strong anti-interference, good long-term stability.

8.Imported diffusion silicon core, more accurate measurement.

Due to the advantages of high precision, good long-term stability and rich functions, the intelligent pressure transmitter is a key component for the modernization and automation of industrial production. Therefore, it is particularly important to ensure the reliability of intelligent pressure transmitters, which have a significant impact on the trouble-free operation of the entire system production process.

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 medium to be measured. Hengqing main technical parameters Power supply: 24VDC output 4 20mA two-wire system Zero adjustable range:

5%。Turndown ratio: 3:

1. Above the range range: -100kpa 0 60mpa. Load characteristics:

The load is within 0 600 (24VDC power supply) to maintain constant current output. Flameproof type D BT4, intrinsically safe type IA CT5 Overpressure limit: 2 times the upper pressure of the shield.

Temperature Range: Process: -20 60 Accuracy Class:

Stability:.

Weight: about 1kg Characteristic analysis.

Folding Mold: Macro Lead Imitation Features:

1.High precision;

2.Range, zero point, external continuously adjustable, diffusion silicon pressure transmitter with good stability, positive migration up to 500%, negative migration up to 600%;

3.two-wire system;

4.Adjustable damping, overpressure-resistant solid sensor design;

5.No mechanical moving parts, less maintenance, light weight (;

6.The whole series has a unified structure, strong interchangeability, and miniaturization (166mm total height);

7.The diaphragm material in contact with the medium can be unilateral overpressure resistance;

8.Low-pressure cast aluminum alloy housing.

What is the purpose of a transmitter? What is the role of a monocrystalline silicon pressure transmitter?

The function of the transmitter is to convert the physical measurement signal into a standard electric signal and supply it to the secondary instrument. Any sensor that can be converted into a standard signal is called a transmitter.

The transmitter converts the different output signals of various sensors into a standard output signal of 0 10V or 4 20mA.

Housing + circuit board + sensor.

The specific material depends on the use environment, which is divided into general environment and corrosive environment, but they are all made of metal.

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, usually consisting of a sensitive element and a conversion element. When the output of a sensor is a specified standard signal, it is called a transmitter.