Working Principle

An intelligent pressure transmitter is a high-precision pressure measurement instrument that integrates microprocessors, digital signal processing, and communication technologies. It is widely used in industrial automation fields such as petroleum, chemical engineering, power, metallurgy, and water treatment for the precise measurement and control of parameters such as pressure, liquid level, and density of liquids, gases, or steam.

Structural Composition

The intelligent pressure transmitter consists of a sensor unit and an intelligent electronic board:

1. Sensor unit: It includes capacitive, diffused silicon or strain gauge pressure sensors, which measure the medium pressure and convert it into an electrical signal.
2. Intelligent electronic board: It is equipped with a microprocessor that amplifies, linearizes, temperature compensates and digitizes the sensor signal, and ultimately outputs a standard signal. Some models support local key adjustment or HART hand-held communicator calibration.

Parameter Typical Value Range Technical Highlights

Product advantages

• High precision and stability: The reference accuracy can reach ±0.1%FS, with automatic temperature, nonlinearity and time drift compensation, and excellent long-term stability.
• Wide range ratio: The range ratio can reach 40:1 to 100:1, suitable for various working conditions and reducing the types of spare parts.
• Bidirectional communication and remote configuration: Supports HART, Profibus, Modbus and other protocols, and can be remotely set parameters and monitor status through hand-held devices or upper computers.
• Self-diagnosis function: Power-on self-check, fault alarm, facilitating maintenance and fault detection.
• Flexible output mode: Standard 4-20mA superimposed with digital signal, optional LCD head, supporting linear or square root output.
• Strong anti-interference ability: Good suppression of electromagnetic interference and radio frequency interference, suitable for complex industrial environments.

Installation Specifications

• Pressure guiding pipe layout: For liquid medium, the pressure guiding pipe should be inclined downward with a slope of ≥ 1/12 to prevent the accumulation of gas and liquid.
• Electromagnetic protection: Shielded twisted-pair cables should be used for signal cables, and the distance from power cables should be ≥ 30 cm, with single-point grounding.
• Explosion-proof sealing: When installing explosion-proof transmitters, ensure that the thread engagement is ≥ 6 turns and the sealing gasket is not aged.

Maintenance Suggestions

• Regular Calibration: Perform zero/ span adjustment using a HART communicator annually; reduce to every six months in high-temperature environments.
• Preventive Cleaning: Wipe the ultrasonic probe every quarter and avoid contact with sharp objects for the capacitive diaphragm.