Digital pressure gauges are sensor devices that transform an applied pressure into an electrical signal. Different pressure-gauging devices are now available in the market. Devices using mechanical deflection include a flexible or elastic element like a diaphragm. These devices respond to pressure changes in the given medium.

Digital pressure gauges that incorporate a bridge circuit use a diaphragm. However, this is only used for detecting changes in the capacitance. Strain-sensitive variable resistors or strain gauges are sometimes used in Wheatstone bridge circuits for taking measurements. Other digital pressure gauges use vibrating elements, thin film, microelectromechanical systems (MEMS) or pistons for sensing pressure changes.

Some devices also use piezoelectric sensors for measuring quasi-state and dynamic pressure. These types of sensors have two modes – voltage and charge. The voltage mode uses an amplifier for converting high-impedance charge to low-impedance output voltage.

Outputs offered by digital pressure gauges

Digital pressure gauges carry out different pressure measurements and show the amount in different units. In terms of units, output is displayed in kilo pascals, pounds per square inch (PSI), centimetres or inches of mercury, milli-bars or bars and feet or inches of water. Other digital pressure devices show measurements in kilograms per square centimetre or ounces per square inch.

Choosing digital pressure gauges needs an analysis of the operational features and performance specifications in the application in which they are to be used. Output signals received from digital pressure gauges can be encoded via frequency modulation (FM), amplitude modulation (AM) or other types of modulation like pulse train or sine wave.

Pressure gauges are used for different application-specific and industrial pressure monitoring applications. Some important uses of pressure gauges include the visual monitoring of gas and air pressure for vacuum equipment, compressors and process lines. Pressure gauges are also helpful in specialty tank applications like fire extinguishers and medical gas cylinders.

Besides visual indication, pressure gauges can also be configured to monitor temperature and offer an electrical output of the indicated pressure. For accurate pressure measurement, it is important to choose a pressure range that can accommodate the anticipated pressure swing to avoid excessive needle movement.

When there is a fluctuation in pressure (pulsation by a compressor or pump) it is better to lower the operating pressure (50% of the complete range). Options for pressure gauge measurement include vacuum measurement, positive pressure, absolute pressure, differential pressure, compound pressure and sealed pressure.

How pressure gauges work

Vacuum measurement switches determine the vacuum pressure (negative pressure). Positive pressure gauge measures the pressure range from zero to higher pressure. Compound pressure gauge determines pressure range from negative (vacuum) to positive pressure.

On the other hand, differential pressure gauges provide the relative pressure in between two different points. If both operating pressures are at a similar point, the measuring element becomes immovable and does not show any pressure. A differential pressure is only indicated when one pressure is lower or higher. Absolute pressure gauges are only used when the pressure measured is interdependent of the fluctuations in the atmospheric pressure.

Pressure gauges are devices that are used in a range of application specific industrial pressure monitoring applications. The uses of pressure gauges include visual monitoring of gas and air pressure for equipment such as compressors and process lines. They are also used in tank applications such as fire extinguishers and medical gas applications.

Besides visual indication, some pressure gauges can also offer electrical output of pressure detection and monitoring of other valuables like temperature. For best results, it is essential to choose a pressure range that accommodates pressure swings and prevents extreme needle movement.

It is always recommended to confine the normal operating pressure to 25% or 75% of the scale. In case the pressure is very variable it’s always worth trying to lower the maximum operating pressure. Pressure gauge measurements that can be taken include vacuum measurement, positive pressure measurement, differential pressure measurement, compound measurement, sealed pressure measurement and absolute pressure measurement.

Functioning of different pressure gauges

Positive pressure gauges measure the pressure range from zero to high, positive pressure. A compound pressure gauge measures the pressure from negative (vacuum) to a positive range.

Differential pressure gauges offer relative pressure between two different points. In case the operating pressure of both points is the same, the measuring element cannot move. Thus, no pressure will be shown on the pressure gauge. On the other hand, differential pressure can be indicated when one pressure level is slightly lower or higher than the other.

There are numerous pressure-gauging technologies available today including digital and analogue pressure gauges. Digital pressure gauges transform the applied pressure into signals and display the readouts numerically. Devices using mechanical deflection include a flexible or elastic element like a diaphragm that reacts to a change in pressure.

On the other hand, there are digital pressure gauges that include a diaphragm and a bridge circuit, but they detect changes in capacitance. Typically, strain-sensitive variable resistors or strain gauges are the basic elements used in Wheatstone bridge circuits that do this measurement. Other digital pressure gauges use vibrating elements, a thin film, pistons or micro electromechanical systems (MEMS) for sensing pressure changes.

There are some devices that use piezoelectric sensors for measuring quasi-state and dynamic pressure. These sensors have two modes:

Voltage mode – uses an amplifier for converting the high-impedance charge into a low-impedance output voltage.
Charge mode – is used for generating a high-impedance charge.

What are digital pressure gauges used for?

Digital pressure gauges perform numerous pressure measurements and display the amount in different units. Absolute pressure is a type of pressure measurement that is relative to a perfect vacuum.

Pressure gauges are sensing devices that are used for monitoring the pressure exerted by a specific operation. In the recent past, there have been several developments in improving the functions of pressure gauges. These advancements greatly help in measuring a decrease and increase in pressure levels.

Pressure gauges are classified into two different types – indirect reading and direct reading devices. The indirect reading pressure gauges display the results when there is a change in certain gas’s property or by measuring the gas density. On the other hand, when a particle change incidentally touches a surface, it will yield some type of pressure. The level of this type of force can be calculated with the help of a direct reading pressure gauge.

Where are pressure gauges used?

Pressure gauges are commonly used in factories, mills and power plants. The pressure gauges are always present in fluid systems where there are pumps and spray nozzles.

Filled gauges and regular or traditional gauges are two types of pressure gauges that are commonly used. The regular or traditional gauges are prone to usual gauge failures. They have sensitive pivots, pinions and connecting links. On the other hand, filled gauges are quite reliable and offer a longer service life.

You can protect the pressure gauge device by using accessories such as pulsation dampeners or snubbers, siphons or pipe coils, shutoff valve and chemical seals. When pressure gauges are equipped with these accessories, your gauge will operate more efficiently.

Digital pressure gauges are pressure measurement devices that convert the applied pressure into signals. The readouts of these signals are numerically displayed. Today, numerous pressure-gauging technologies are available. Digital pressure gauges include a bridge circuit and diaphragm. However, it only detects the changes in capacitance.

Typically, strain sensitive variable resistors and strain gauges are used as components in Wheatstone bridge circuits to perform measurement. On the other hand, devices that utilise mechanical deflection include a flexible or elastic element like a diaphragm which responds to the changes in pressure. Other types of pressure gauges use vibrating elements, pistons, thin film or micro-electromechanical systems (MEMS) to sense pressure changes.

Some pressure sensing devices also use piezoelectric sensors to measure quasi-state and dynamic pressure. Generally, these types of sensors have two different modes; voltage and charge. While the charge mode produces a high-impedance charge, the voltage mode uses an amplifier for converting the high-impedance charge into low-impedance output voltage.

The advantages of digital pressure gauges

The digital pressure gauge performs a number of pressure measurements and displays the amounts in different units. An absolute pressure is a type of pressure measurement that is relative to perfect vacuum. Typically, the vacuum pressure is always lower than the atmospheric pressure.

Types of pressure measurement

Gauge pressure is one of the most common types of pressure measurements. It is relative to the local atmospheric pressure. Sealed gauge pressure is the other type of pressure measurement that is relative to an atmosphere of pressure (oz) of the sea level. Similarly, differential pressure reflects the actual difference between the two input pressures.

Digital pressure gauges are pressure measurement devices that convert the applied pressure into signals. The readouts of these signals are numerically displayed. Today, numerous pressure-gauging technologies are available. Digital pressure gauges include a bridge circuit and diaphragm. However, it only detects the changes in capacitance.

Typically, strain sensitive variable resistors and strain gauges are used as components in Wheatstone bridge circuits to perform measurement. On the other hand, devices that utilise mechanical deflection include a flexible or elastic element like a diaphragm which responds to the changes in pressure. Other types of pressure gauges use vibrating elements, pistons, thin film or micro-electromechanical systems (MEMS) to sense the pressure changes.

Some pressure sensing devices also use piezoelectric sensors to measure quasi-state and dynamic pressure. Generally, these types of sensors have two different modes; voltage and charge. While the charge mode produces a high-impedance charge, the voltage mode uses an amplifier for converting the high-impedance charge into low-impedance output voltage.

Advantages of digital pressure gauges

The digital pressure gauges perform numerous pressure measurements and display the amounts in different units. An absolute pressure is a type of pressure measurement that is relative to perfect vacuum. Typically, the vacuum pressure is always lower than the atmospheric pressure.

Types of pressure measurement

Gauge pressure is one of the most common types of pressure measurements. It is relative to the local atmospheric pressure. Sealed gauge pressure is the other type of pressure measurement that is relative to 1 atmosphere of pressure (oz) of the sea level. Similarly, differential pressure reflects the actual difference between the two input pressures.