A pressure transmitter is a crucial device indispensable in the field of industrial automation. It can convert the pressure signals of gaseous or liquid media into standard electrical signals (such as 4 - 20mA, 0 - 10V, or digital signals), providing data support for the monitoring, control, and optimization of industrial processes. Its high - precision and high - stability characteristics make it widely used in complex industrial scenarios such as petrochemical, power, and environmental protection industries.

 

Core Functions

1. Real - time Monitoring and Control

The pressure transmitter captures pressure changes in real - time through the pressure - sensing element and converts them into transmittable electrical signals for use in control systems such as PLC and DCS. For example, in oil pipelines, valve openings can be adjusted in a timely manner by monitoring pressure fluctuations to ensure transportation safety.

2. Remote Data Transmission and Integration

It supports wired or wireless communication protocols and can transmit pressure data remotely to the central monitoring platform, enabling centralized management of cross - regional equipment. For example, pressure data in urban gas pipe networks can be transmitted to the dispatching center through Internet of Things technology to prevent leakage risks.

3. Safety Warning and Linked Protection

When the pressure exceeds the set threshold, the device can trigger audible and visual alarms or automatically cut off dangerous processes. For example, abnormal pressure in a chemical reactor may trigger a chain shutdown to avoid explosion accidents.

4. Process Automation Optimization

As the "sensory terminal" of the automation system, the pressure transmitter works in coordination with other instruments to achieve closed - loop control of the process flow, such as precise adjustment of slurry pressure in paper mills.

Application Areas

- Petrochemical Industry: Used for pipeline flow monitoring, tank level calculation (in combination with throttling devices), and chemical reaction pressure control.

- Power and Urban Gas: Boiler pressure monitoring and gas pipe network leakage detection, requiring long - term high stability and anti - interference ability.

- Environmental Protection and Water Treatment: Pressure monitoring in sewage treatment pumping stations and pressure maintenance in fire - fighting water systems.

- Metallurgy and Manufacturing: Furnace pressure monitoring in high - temperature and high - pressure environments and precision control of mechanical hydraulic systems.

- Aerospace and Shipbuilding: Fuel delivery pressure management and cabin sealing detection.

 

Classification and Working Principles

Based on the conversion principle, pressure transmitters are mainly divided into the following types:

1. Capacitive Type: It uses the change in capacitance caused by the deformation of the measuring diaphragm and converts it into an electrical signal. This type has high precision and fast response and is widely used in micro - differential pressure scenarios.

2. Strain - gauge Type: It changes the resistance value through the deformation of the metal strain gauge and is suitable for high - pressure measurement.

3. Frequency Type: It converts pressure changes into frequency signals and has strong anti - interference ability.

4. Inductive and Force - balance Types: Signal conversion is achieved through electromagnetic induction or mechanical force balance and is mostly used in traditional industrial scenarios.

 

Its core working principle is based on mechanical effects and electrical conversion:

- Piezoelectric Effect: Some crystal materials generate charges under pressure, directly generating electrical signals.

- Strain - gauge Technology: Pressure causes the deformation of the elastic element, resulting in a change in the resistance of the attached strain gauge, and the signal is output through the Wheatstone bridge.

- Capacitive Sensing: The pressure difference changes the distance between the capacitor plates, which is demodulated into a standardized current/voltage signal through the oscillation circuit.

 

Performance Advantages

- Environmental Adaptability: The stainless - steel shell and isolation diaphragm design can resist chemical corrosion, high temperature, high pressure, and vibration impact.

- Intelligent Compensation: It integrates a temperature compensation algorithm to eliminate the influence of the external environment on measurement accuracy.

- Low Power Consumption and Long - term Battery Life: Battery - powered combined with a low - power circuit design can work continuously for more than 5 years.

- Data Reliability: The built - in memory can save data when the network is disconnected, and it is equipped with a display for on - site real - time viewing.

- Convenient Configuration: It supports USB or wireless connection, allowing for quick adjustment of the range and parameters through mobile devices.