Everything You Need To Know To Find The Best Industrial Pressure Measurement Devices

Sep. 01, 2025

Ways to Measure Pressure in Industrial and OEM Applications

If you are working in an industry that requires instrumentation to measure and monitor pressure in a system, you already know the basic principle of pressure measurement. According to Pascal's Law, pressure is proportional to the force and inversely related to the area over which the force is applied. In other words, pressure is equal to force per unit area.

You will get efficient and thoughtful service from gallopsensor.

Figure 1: Pressure Equation.

Different systems and applications require different types of pressure measurement instruments. For example, mechanical pressure gauges may be used as visual indicators of pressure levels throughout a process. Conversely, pressure transducers or transmitters can sense changes in a system’s pressure and send a signal to a control room. If you are new to your industry and want to learn more about pressure instruments, this article will give you a high-level overview of how to read pressure, definitions of pressure types and the instruments used to measure pressure.

Ashcroft is a recognized global leader in pressure instrumentation and is a trusted authority for related information. When you are done reading, you will find additional resources related to pressure measurement that may interest you.

How do you measure pressure?

In the U.S., pressure is measured as pound force per square inch or psi. Note, in other parts of the world, pressure is measured in different systems of units. The three main systems are the American System, Systeme International (SI) and the Meter, Kilo, Second (MKS). See below for a full list:

Figure 2: Pressure System of Units.

High pressure measurements generally range above 15 psi while low-pressure measurements range below 15 psi.

Figure 3. PSI Ranges.

Low pressure is best explained using a manometer as an example. In Figure 4 below, without any pressure applied to the open tube manometer, the water level is even on both sides of the tube. When you add a small amount of pressure from the bicycle pump to one side of the tube, it displaces the water in the tube.

The side with the pressure applied goes down while the other side goes up. When you measure the total displacement, you measure the pressure applied. In this example, the displacement is 4 inches, so the pressure applied is 4 inches of water.

Figure 4: Low-Pressure Manometer.

Types of pressure measurement.

Absolute Pressure. A measured reference to absolute vacuum (zero pressure). Absolute vacuum occurs when air is completely absent. There is no negative absolute pressure.

Figure 5: Absolute Pressure.

Gauge Pressure. A positive pressure greater than atmospheric or barometric pressure using ambient pressure as the reference.

Vacuum Pressure. A negative pressure less than atmospheric or barometric pressure using ambient pressure as the reference.

Figure 6: Gauge and Vacuum Pressure.

Note: there may be specific requirements for gauges that measure both positive pressure and negative pressure, also known as a gauge with a compound range or scale.

Differential Pressure. The difference between two different pressure points in a system. This is often called “DP”, “∆P” or “DeltaP”.

Related links:
Prosthetic Covers | PrimeCare

Are you interested in learning more about Industrial Pressure Measurement Devices? Contact us today to secure an expert consultation!

Figure 7: Differential Pressure.

Static Pressure. The maximum working pressure (MWP) in a system with or without flow.

Single-Sided Static Pressure. The maximum pressure that can be applied to one side of an instrument while the other side is open to the atmosphere.

Proof Pressure. The maximum pressure a gauge can withstand without plastic deformation of the pressure element. (ASME B40.100-)

Burst Pressure. The maximum pressure above which the pressure element assembly will no longer hold pressure.

Pressure measurement applications.

Depending on the application, your instrument will have different requirements for pressure type, psi and other factors. Here are just a few of the thousands of applications where you would expect to see pressure measurement instruments in your daily life.

Figure 8: Pressure Measurement Applications.

Whether your application is measuring high-pressure or low-pressure, Ashcroft offers an extensive range of measurement instruments to address your specific needs. For instance, our process gauges and industrial gauges provide visual indicators to operators, while our transducers with advanced sensing technology will communicate pressure measurements to a control system. Visit Ashcroft.com/products to our complete line.

Go beyond the basics.

Now that you know the fundamentals of pressure measurement are you ready to expand your knowledge? Here are a few related articles that can get you started.
• How Much Do Mechanical Pressure Gauges Cost?
• What is a Differential Pressure Gauge?
• Choosing a Pressure Gauge for Hydrogen Applications
• The difference between a pressure transducer and a pressure transmitter
If you prefer to speak with someone directly, feel free to contact one of our product experts with any questions you may have.

Questions you need to ask before choosing your industrial pressure ...

Selecting the appropriate industrial pressure transmitter poses a significant challenge. When determining the ideal transmitter for your specific application, it’s crucial to ask the right questions during the decision-making process.

Question 1: What is the type of measurement?

Pressure measurement – The pressure transmitter’s most prevalent usage involves measuring both pressure and vacuum. In this application, the sensor experiences pressure, typically from sources like pumps or compressors
Level Measurement – The sensor gauges the variance in elevation between two locations. It can be employed for determining the height of a liquid column
Flow measurement – Differential pressure flow measurement relies on the pressure contrast within a moving fluid, facilitated by specialized primary components. These flow meters are instrumental in quantifying the flow of both liquids and gases within pipelines
Density measurement – Utilizing a differential pressure transmitter for density measurement proves to be an efficient approach for assessing the density of liquids

Question 2: What is the nature of the fluid?
Considering the composition of the fluid, whether it’s gas, liquid, or vapor, holds significant importance in process measurement. Understanding the essential characteristics of the fluid is crucial for selecting the appropriate sensor for your industrial process.

Question 3: What type of pressure is being measured?
The pressure type you intend to measure—Differential, Gauge, Absolute, or Vacuum—is a crucial factor in selecting the appropriate pressure transmitter.

Pressure transmitters designed for measuring pressure differentials and low pressures are highly suitable for tasks like monitoring filter clogging and determining fluid flow rates, especially when paired with depressurizing devices
Relative or vacuum sensors within pressure transmitters are better suited for gauging static pressure or negative gauge pressure, typically when the sensor is exposed to pressure from sources like pumps or compressors.
Absolute pressure transmitters are utilized in applications where pressure measurements are referenced relative to a perfect vacuum

Question 4: What is the fluid temperature?
Fluid temperature is a critical aspect to contemplate when choosing a pressure transmitter. These transmitters are typically engineered to function effectively with liquids, gases, or steam within specific temperature thresholds. The minimum and maximum operational temperature parameters of pressure transmitters play a significant role in selecting a sensor for prolonged usage. In instances of elevated temperatures, employing pressure transmitters with diaphragm seals becomes imperative to safeguard the sensor electronics from the process measurements.

Question 5: What is my measurement range?
The pressure range stands as the ultimate factor to ponder when deciding on a pressure transmitter. It’s imperative to select the zero and span parameters carefully to encompass the relevant range while avoiding surpassing the upper or lower limits necessary for accurate measurements.

Question 6: How corrosive is the fluid?
The corrosive nature of the fluid, whether contaminated or chemically aggressive, must be carefully considered when choosing a pressure transmitter. Certain fluids can corrode sensitive materials under specific conditions, influencing the selection of materials for components in contact with the fluid. This selection significantly impacts the sensor’s lifespan. It’s essential to verify the compatibility of the fluid with the construction materials of your pressure transmitter.

Question 7: What process connections are planned?
The variety of process connections—whether flanged, threaded, screwed, or hygienic—is another aspect to weigh when selecting the appropriate pressure transmitter. Different types of process connections cater to specific application needs:

Flanged connections enable high pressure ratings with minimal pressure drops
Threaded connections facilitate easy linking of hoses, tubes, and valves
Hygienic connections ensure food safety during processing through sanitary designs

Question 8: What are the environmental conditions?
Environmental conditions within the application, including temperature, humidity, explosive atmosphere, dust, electromagnetic compatibility (EMC), vibrations, and safety integrity level (SIL), are additional crucial considerations when selecting a pressure transmitter. It’s essential to comprehend the operational context of the pressure transmitters and verify their ability to endure all potential conditions in their application environment. Furthermore, determining if your application necessitates specific safety certifications is imperative. Selecting a pressure transmitter with certifications such as SIL2 or ATEX, IECEx, etc., ensures compliance with safety requirements.

Question 9: What are the specific requirements of my application?
Specific requirements tailored to the application:

For more information, please visit temperature measurement device.

Comments

All Comments (0)

Previous: 12m Flat Pack Container House: Trends for 2025
Next: Prosthetic Covers | PrimeCare