Differential pressure sensors offer functionality beyond their primary purpose. Explore the unexpected measurements and applications that these multi-purpose sensors can be adapted to support.
Measurement & Instrumentation Guides
Guidance and reference articles for sourcing, setting up and using measurement equipment.
Measuring flow rate of a liquid or gas using a dp sensor
An introduction to the dp flow method of using a differential pressure sensor for measuring the flow of liquids and gases.
Measuring density of a liquid using a dp sensor
This guide provides an overview of methods for measuring liquid density using differential pressure sensors in various tank configurations and conditions.
Measuring liquid level in a tank using a dp sensor
Differential pressure sensors can be used to measure liquid level in a tank. Here we will explain how a DP sensor is used to measure liquid level.
Measuring vacuum as a negative gauge pressure using a dp sensor
Learn how a differential pressure sensor (dp sensor) can be used to measure a partial vacuum as a negative pressure relative to local surrounding air pressure.
Measuring vacuum as an absolute range using a dp sensor
Find out how to use a differential pressure sensor (dp sensor) to measure a partial vacuum as a positive pressure relative to full vacuum.
Measuring barometric pressure using a dp sensor
Learn the method to convert a differential pressure (DP) sensor for barometric pressure measurement.
Measuring absolute pressure using a dp sensor
Learn the method to convert a differential pressure (DP) sensor for absolute pressure measurement.
Measuring gauge pressure using a dp sensor
Differential pressure sensors can double as gauge pressure sensors. Here we will explain how a DP sensor is used to measure gauge pressure.
How do you choose the correct pressure range for a pressure sensor
The pressure range is the most complicated and confusing specification parameters to define for a pressure sensor.
Can you have a minus 20 psi gauge vacuum measurement range
Is it possible to have a vacuum pressure measurement device with a -20 to +50 psi gauge pressure range, since I’ve never seen a pressure instrument with a range greater than -15 psi?
Output signal orientation for a negative gauge pressure range
Since a negative pressure range works backwards to a positive gauge or an absolute pressure range, and that zero pressure corresponds to a full scale measurement, it has led to the use of both a forward and reverse output signal to measure suction or vacuum pressure in relation to ambient atmospheric air pressure.
Measuring negative pressure using a positive differential pressure range
How can you use a differential pressure measurement device to measure a negative pressure if it has been factory configured to measure a positive pressure range without making any adjustments to the electronics or the signal output?
What does negative and positive gauge pressure mean
You may not be aware but nearly every pressure measurement device you are using has a positive or negative gauge reference.
Can you measure vacuum using a gauge pressure range
The most common type of pressure range for pressure measurement instrumentation is one which has a gauge reference. So if you want to measure vacuum pressure, it would be convenient to use a gauge pressure device which is the most widely available pressure range format.
What is the difference between vacuum and absolute pressure
Often you will see a measurement of vacuum pressure described as an absolute pressure reading, so is there any difference between the two?
Determine range of pressure gauge needed to measure force generated by hydraulic press
Work out what pressure gauge is needed based on the bore size of the cylinder and the maximum force generated by a press.
Low Pressure Range
Low range pressure sensors, gauges, loggers and calibrators for measuring low pressures on filtration sytems, ventilation fans, air conditioning & handling systems.
High Pressure Range
High range pressure sensors, digital test gauges, loggers & calibration pumps for measuring and testing hydraulic equipment
Differential Pressure Sensors
Differential pressure sensor product selection guide for sensors used to measure the difference in pressure between two points.
How do you measure flow rate with a dp cell
How do you use a dp cell measuring a span of 0-500 mmH2O with an o/p of 4-20 mA to control a flow rate of 0-1000 L/h for a flow meter range?
Vented Gauge
Vented Gauge (VG) is a pressure referenced to atmospheric pressure via a vent path on the reverse side of the pressure sensing diaphragm.
Compound Pressure Ranges
Compound pressure ranges include both a positive and negative pressure range in one pressure measurement device.
Absolute Pressure
A guide to absolute pressure measurement including explanations, applications and choice of products for measurements using a absolute reference.
Hydrostatic Pressure
Hydrostatic pressure is the pressure that is generated by the weight of liquid above a measurement point, when the liquid is at rest.
Differential Pressure
A guide to differential pressure measurement including explanations, applications and choice of products for measuring differential pressure
Negative Gauge Pressure
Negative Gauge Pressure is the difference in pressure between any vacuum and atmospheric pressure. The maximum possible negative gauge pressure is always limited by the current ambient atmospheric pressure, which constantly varies, but is typically around 1 bar absolute.
Reference Pressure
Reference Pressure is the pressure present on the reverse or negative side of a pressure sensing element.
SG – Sealed Gauge
Sealed Gauge (SG) is a type of reference pressure measured relative to a fixed pressure of approximately 1 bar absolute.
Static Line Pressure
Static Line Pressure is the total pressure present at a particular point along a pressurised pipe.
Suction Pressure
Suction pressure is a negative difference in pressure generated between two points which draws a gas or a liquid from a higher to a lower pressure state.
Wet/Dry
Wet/Dry describes a dp measurement device for use with a liquid on the positive pressure side and a dry/non-condensing gas on the negative pressure side.
Wet/Wet
Wet/Wet describes a differential pressure measurement device which is compatible with liquid on both the positive and negative side process connections.
Rangeable
Rangeable describes a type of measurement instrument that has an output signal which can be adjusted by the operator to a different scaling.
Vented Cable
Vented Cable has a vent tube running through the inside of the cable to provide a vent path between the electrical connections at either end.
MSL – Mean Sea Level
MSL or Mean Sea Level is the average height of the ocean surface. Mean sea level is a significant datum reference for meteorological and altitude related pressure measurements, e.g. standard atmospheric pressure at mean sea level is 1013.25 hPa or 29.92 inHg.
Gauge Reference Pressure
Gauge reference pressure is a pressure measured relative to atmospheric or barometric pressure. The most used pressure reference is gauge pressure which is signified by a (g) after the pressure unit (e.g. 30 psi g), and means that the pressure measured is the total pressure minus atmospheric pressure. There are two types of gauge reference […]
FS – Full Scale
Full Scale (FS) is the difference between the lowest and highest possible measurement point
Dry/Dry
Dry/Dry describes a differential pressure measurement device which is only compatible with dry/non-condensing gas on both the positive and negative pressure side.
Burst Pressure
Burst pressure is a design safety limit which should not be exceeded. If this pressure is exceeded it may lead to mechanical breach and permanent loss of pressure containment.
Vacuum
This guide provides an overview of measuring vacuum pressure including suggested vacuum measurement products and question & answers.
Using Sealed Gauge Reference Pressure Sensing Devices
Sealed gauge or SG is a type of pressure reference typically used when a vented reference is not possible because of the type of sensing technology or the need to provide secondary containment overpressure protection.
Bidirectional
Bidirectional is typically used to indicate that a particular parameter such as an electrical signal or measurement range will generate values in both the positive and the negative direction. For example a sensor which has a -10 mbar to + 10 mbar gauge pressure range with a 0 to 10 Vdc output is said to […]
Overpressure Protection
Overpressure is used to describe a condition where the pressure value has exceeded operational limits or a threshold pressure.
What is the difference between sealed gauge and vented gauge reference?
Gauge reference pressure measuring devices read pressure relative to atmospheric pressure. This ensures that the pressure reading is nominally zero when the pressure on the device is released.
Simulating 8000 foot altitude with a pressure gauge
We are trying to simulate an environment of 8000 feet in altitude inside a cylinder. We are located in an area that is 200 feet above sea level.
What is difference between working, burst and over pressure
I have a confusion regarding the difference between the maximum working pressure, overpressure and burst pressure for pressure transmitters.
Converting non-vented depth readings & barometric pressure to true depth
I have level data from a non-vented transducer & barometric pressure data, how do I determine the true depth?
Not Reading Zero when Pressure is Vented to Atmosphere
It is not unusual for a pressure measurement device to read slightly above or below zero with no pressure applied.
Barometric Pressure
A guide to barometric pressure measurement including explanations, applications and choice of products for measuring barometric pressure.
Using an Absolute Sensor to Measure Gauge Reference Pressure
When it is necessary to present gauge reference pressure data, an absolute pressure sensor can be used in some situations if a gauge pressure sensor is not available. An absolute pressure sensor will measure total pressure independent of atmospheric pressure changes, unlike a gauge pressure sensor which measures pressure relative to atmospheric pressure. To convert […]
Does the type of Engineering Units matter for Pressure Transmitters
When selecting a part number for a pressure transmitter you will need to choose a pressure range. Usually a manufacturer will designate pressure ranges in the most common unit used by it’s customers. For the USA the most common unit is psi and for Europe it is bar, but what if you are working with […]
What does the suffix a, abs, d, dp and diff, g, rel and sg mean after the pressure units in a pressure range?
There is a loose convention across manufacturers for designating the type of reference that a pressure sensing device has, which can be confusing if you are unfamiliar with specifying this often overlooked but critical specification parameter.
Measuring the difference in air pressure between rooms
Monitoring and controlling the pressure in a room is a critical parameter in many indoor environments where the climate must be maintained at a particular temperature, humidity and cleanliness/containment level.
What is the difference between gauge and absolute pressure measurement
Determining whether you need gauge or absolute reference pressure is a very important to selecting the right pressure range for a pressure instrumentation.
Measuring liquid level in a sealed tank with a hydrostatic pressure sensor
In order to measure the level of a liquid using a pressure sensor you must be able to subtract the pressure of the gas at the top of the tank.
Determining the hydrostatic pressure range for a tank level sensor
There are many ways to measure the height of a fluid and one of the most popular is to use a pressure sensor.
Using absolute pressure sensors to measure hydrostatic level
Venting a gauge reference hydrostatic pressure sensor to the outside air is not always possible and an absolute reference sensor has to be used instead.
Selecting a pressure range for optimal service life and accuracy
What pressure range you select for a pressure measurement application affects the accuracy and the service life of a pressure transducer.
Measuring vacuum with negative gauge or absolute ranges
There are two reference points for measuring a vacuum pressure.