The Differences Between Pressure Transmitters and Pressure gauges

Both pressure transmitters and pressure gauges are instruments used to measure pressure under various working conditions, yet they differ significantly in working principles, functions, and application scenarios.

Working Principles and Output Modes

Pressure Gauges: They utilize elastic components (e.g., bourdon tubes, C-type tubes) to sense pressure. Through mechanical transmission, a pointer directly displays the pressure value on a dial. The output is a scale indication, and the device itself has a built-in display function.

Pressure Transmitters: They convert pressure signals into standard electrical signals (e.g., 4-20mA DC). They must be connected to secondary instruments (e.g., ammeters, PLCs) for data display, with outputs in the form of current or voltage signals, which are used for remote transmission and automated control.

Accuracy and Calibration

Pressure Gauges: They feature relatively low accuracy (have  ±1%, ±1.6%, or ±2.5%). Calibration requires metrological qualification and usually involves multiple checkpoints (e.g., 5 points), with possible variations in hysteresis errors.

Pressure Transmitters: They offer high accuracy (typically ±0.1%, ±0.25%, or ±0.5% F.S.). Calibration demands high-precision standard instruments, and intelligent models generally only require zero-point and full-scale calibration.

      Pressure Guages calibration                                                       Pressure Transmitters Calibration

Application Scenarios

Pressure Gauges: They are suitable for occasions where accuracy requirements are not stringent and only on-site visual readings are needed, such as distillation workshops and clean production workshops in pharmaceutical manufacturing, pipelines at oil drilling sites, ship engine rooms, automation equipment, and pipeline systems in food processing plants.

Pressure Transmitters: They are applied in industrial automated control systems that require remote transmission, recording, and regulation of pressure data, such as chemical, petroleum, water treatment, shipping, and automation equipment industries.

Installation and Maintenance

Pressure Gauges: They can be directly mounted on pipelines or equipment, with simple maintenance procedures.

Pressure Transmitters: Factors such as power supply, explosion protection, anti-freezing, and anti-interference must be taken into account during installation, and their mounting locations should avoid high temperatures, vibrations, and corrosion.

Our Huaihua brand back-mounted stainless steel pressure gauges are used in automatic equipment (manufacturers of automatic equipment).

In short, pressure gauges are suited for simple and intuitive pressure measurement, while pressure transmitters are designed for high-precision and automated control needs. The selection between them should be determined based on specific working conditions and accuracy requirements.

In the next time, we will special discuss the differences in maintenance between pressure gauges and pressure transmitters.