Frequently Asked Questions

Need Some Help?

There are several names to describe a Pressure Sensor. In general a Pressure Transducer has a mV output, Pressure Transmitter has an amplified output but don’t forget there are pressure gauges which give a visual indication of the measured pressure, or even pressure switches which can be set to trigger at a given pressure level. Other terminology extends to pressure capsules, pressure sensing elements, packaged pressure sensors, digital output pressure sensors for example.

There are many types or variants of pressure sensor depending mainly on the application where the sensor will be used. These are electro-mechanical devices and in general are fitted directly to the medium being measured. There are many considerations such as temperature, size of the pressure sensor, corrosive environment, ingress protection, signal output required, material of construction, cost.

Pressure sensors start with the sensitive element that will convert the pressure of a gas or liquid into an electrical signal. The easiest way to understand this principle is to consider them as strain gauges. There are many technologies of pressure sensing elements, each has a unique feature which offers a better solution for the application. Piezo resistive technology example is great for volume applications, gas measurement, barometrics however for liquids there are some compromises to be made. For liquids, it is very common to have a diaphragm to isolate the pressure sensing element which in itself presents challenges with diaphragm materials, sensing technology, size, accuracy etc.

There are several outputs available for Pressure Sensors. The most common by far is an amplified output (referred to as analogue output) such as 4-20mA, 0-5 V, 0-10 VDC for example. Digital outputs such as SDI, I2C, RS-485 or RS-232 are available as an option on most Pressure sensor families however reduce the frequency response, but would increase the user flexibility and accuracy of the sensor. On some Pressure sensors, mV output is available which delivers an excellent frequency response but may need some signal conditioning.

Data acquisition is the process of sampling signals measuring real world physical parameters and storing the signals as digital numeric values that can be viewed and analysed on a computer. Data acquisition systems are often abbreviated as DAQ or DAS. Data acquisition systems consist of sensors, signal conditioning circuity, analogue to digital converters and data storage, and may also include visual displays.

An example of data acquisition is measuring pressure and vibration at multiple locations on a component under test in a component test cell and storing and displaying the data on a computer. The acquired data can also be analysed after the test.

The purpose of data acquisition is to acquire and store data from a product, system or component under test or in operation. The data is used to improve the performance, efficiency, safety or reliability of the product. It is carried out by the manufacturer or user of the product either in the R&D stage or during operational use.

Data acquisition is the process of sampling signals measuring real world physical parameters and storing the signals as digital numeric values that can be viewed and analysed on a computer.

Types of data acquisition can be classified by their use environment including mobile, portable, laboratory, test cell; as well as their acquisition speed including high speed, low speed and quasi-static; or channel count including high channel count, medium channel count and low channel count.

An inclinometer or clinometer is a gravity referenced sensor used for the measurement of angles of slope, elevation or depression of an object. With correct selection they can measure horizontally or vertically. Equally they can be used for platform levelling as well as embankment monitoring.

Accuracy of inclinometers is dependent on the technology used within the sensor, tolerances of machined parts and the calibration methods used. The most common technology is MEMS (Micro-electromechanical system) which will offer accuracies between 0.3 degree for an industrial to 0.002 degree for a high accuracy sensor. It is important to remember that the smaller the inclination measured, the better the accuracy that will be derived.

There is no real difference between an inclinometer and a clinometer however, clinometers can be used to measure slope and is a more manual device. They have several names including tilt sensor, tilt meter, slope gauge, pitch & roll indicator.

Care must be taken to understand digital inclinometer as it can either mean an inclinometer with a digital output or have a digital screen which shows the output. By far the most common is an inclinometer with a digital screen, used for levelling in construction. Digital output inclinometers are usually high performance and high accuracy sensors.  

There are several different technologies used for inclinometers but essentially they all have the same purpose.  They measure the inclination, or angle of an object with respect to the force of gravity. This value is given as an output in an analogue or digital signal from the sensor which varies proportionally to the angle and range of the sensor. 

Inclinometers can be made using several technologies and each has its own pros and cons. Most inclinometers are for static applications such as the three types below. 

  • Fluid inclinometers use a small bowl-shaped container with a conductive fluid inside.  As the sensor is rotated, the fluid moves around the bowl due to gravity creating an output signal which varies accordingly. These devices are best for slow-moving applications. The fluid can be affected by external vibrations which may cause mis-reads caused by wave-like motion in the sensor. 
  • MEMS inclinometers use a Micro Electro-Mechanical System which is etched onto a silicon chip.  The MEMS device operates similar to a pendulum with the fall of the pendulum always pointing downwards due to gravitational pull. As the mechanical structure is so small it allows for fast movements but can also be affected by external vibrations which may cause the inclinometer to behave like an accelerometer.
  • Servo inclinometers also known a force-balance inclinometers operate with a mass mounted in an electromagnetic field. As the mass is subjected to motion, the sensor adjusts the electromagnetic flux to keep the mass in the centre of the field. The amount of correction required is converted to an output signal which is proportional to the inclination of the sensor. This method can be very accurate, but is also very slow in reaction. Often the mass is damped in oil to prevent over-compensation. 

For dynamic applications, or where vibration or accelerations are present the technology used changes.  In these cases a combination of accelerometers and gyroscopes are used to calculate the angular change of the sensor these often also use MEMS technology. Many of these devices have a digital output and have an internal processor to calculate the inclination angle relative to gravity. Some of these sensors can also be used as an IMU (inertial measurement unit) depending on the output options of the signal.

An inclinometer or clinometer is used for measuring slopes or angles of elevation. Some inclinometers have specific ranges and will only be able to measure small angles, whereas others can measure any angle up to a full 360 degrees of rotation. Wider range inclinometers tend to have lesser accuracy so your choice of sensor may not only depend on the range, but also the tolerance or accuracy required of the measurement. So yes an inclinometer can be used as a level within the specified range of the model chosen.

The majority of inclinometers require a reference point to calculate the angle of inclination of a surface or slope.  We use the gravitational pull of the earth as the reference and so gravity is required for most inclinometers to operate. Therefore most inclinometers are not suitable for use where there is no, or insignificant gravitational pull.

The differential pressure sensor is used to measure the pressure drop between two points in the exhaust manifold. At one point, it reports the charge status of the particle filter and monitors its function.

A linear potentiometer is a type of sensor used to measure displacement (length) along a single axis. They can be mounted vertically or horizontally as the application demands. Linear potentiometers have an internal shaft with a wiper blade which slides over a conductive track creating a potential divider.

Linear potentiometers can be used in many applications including motor sport for suspension travel, Automotive road load data (RLD), Medical, Robotics, Mobile vehicles and Civil/Structural measurements.

There are 4 main types of potentiometer and each is used based on the application. Slide, Dual Slide, Multi-Turn Slide & Motorised fader potentiometer.

Both sensor types have a potentiometric output. Linear potentiometers measure linearly along a single axis (Straight line) whereas Rotary potentiometers measure rotational movement.

A linear potentiometer is a length of resistive track which when connected to a power source acts as a variable potential divider using a wiper contact which is moved along the resistive track.  In most cases the resistance is in the region of 1000 to 10000 ohms and is made from conductive plastic or printed conductive ink. Some high-power linear potentiometers are made from a cylinder with a thin wire wound around it which can dissipate more heat than a conductive plastic device.

The connection of the linear potentiometer is always for the negative and positive power supply to be connected either end of the track, and the output to be taken from the wiper connection which will give a voltage output proportional to the position of the wiper between the two ends.

A linear potentiometer is made with a resistive track that is the same uniformity along the full length.  This allows the change of signal to be linear in proportion to the position of the wiper from end to end.  A logarithmic potentiometer has a varying resistance of track along the length causing a more rapid change at one end compared to the rate of change for the same distance at the other end. 

Linear potentiometers are used for measuring lengths and for applications requiring a proportional output to distance moved, however logarithmic potentiometers are used where a rapid change is required at the start or the end of the movement and a smaller change in signal the further the distance travelled.  Logarithmic potentiometers are more commonly found in audio, motor, or lighting control applications where linear potentiometers are found in measurement applications.

The actual acronym for LVDT is Linear Variable Differential Transformer. It is a common type of electromechanical transducer that can convert the linear motion of an object to which it is coupled mechanically into a corresponding electrical signal. Other acronyms are Linear Variable Differential Transducer, Linear Variable Displacement Transducer but in essence they are all the same meaning. 

Principally, LVDTs (Linear Variable Differential Transformer) is used the measure linear displacement. There are many different variants available, but an LVDT can have a separate core making the sensor non-wearing and have a very long cycle life or used for extreme cycle applications. Some LVDTs are designed for very high temperatures to 550 Deg C. 

LVDT Position sensors have many applications not limited to Civil/Structural monitoring, seafloor wellheads, oil & gas platforms, desalination systems and satellite controls. Special versions can be used for Steam or Gas turbines, high nuclear/radiation environments, subsea & marine.

Advantages include low power consumption, no friction losses as non-contact, very high resolution. Disadvantages include the need for additional set up compared to other devices, extra signal conditioning, large size relative to measurement, can be affected by external factors such as temperature.

Pressure Sensor:

A pressure sensor is a device that measures the pressure of a fluid or gas and converts it into an electrical signal. It is designed to detect changes in pressure and provide an output that corresponds to the measured pressure. Pressure sensors can be based on various principles, such as piezoresistive, capacitive, or piezoelectric, and they are often used in a wide range of applications, including industrial processes, automotive systems, medical devices, and consumer electronics.

Pressure Transmitter:

A pressure transmitter is a type of pressure sensor that is specifically designed to provide a continuous and proportional output signal, typically in the form of a 4-20 mA current loop or a digital signal. It measures the pressure and converts it into an electrical signal that can be transmitted over long distances without significant loss or interference. Pressure transmitters are commonly used in industrial applications where precise pressure measurement and transmission are required, such as in process control systems and automation.

Pressure Transducer:

The term "pressure transducer" is commonly used interchangeably with "pressure sensor" or "pressure transmitter." In general, a pressure transducer refers to a device that senses pressure and converts it into an electrical signal however is not amplified, such as a mV output. So, both pressure sensors and pressure transmitters can be considered as types of pressure transducers.

A position sensor is a type of sensor that measures the position of an object, typically with respect to a reference point or axis. Position sensors are used in a wide range of applications, including robotics, manufacturing, and automotive systems.

There are several types of position sensors available, including optical sensors, magnetic sensors, capacitive sensors, and inductive sensors. Each type of sensor has its own advantages and disadvantages, and the best choice will depend on the specific application.

Position sensors work by detecting a change in position and converting that change into an electrical signal. The exact mechanism for detecting position varies depending on the type of sensor, but most use some form of physical measurement or change in an electromagnetic field.

Position sensors are used in a wide range of applications, including robotics, manufacturing, automotive systems, and aerospace. They are used to control the position of robotic arms, detect the position of moving parts in machines, and provide feedback for control systems.

The accuracy of a position sensor depends on several factors, including the type of sensor, the quality of the sensor, and the environment in which it is used. In general, position sensors can be very accurate, with some sensors capable of measuring positions to within microns.

A current transducer is a transducer used for measuring the current flowing in a wire or conductor. Current transducers can be used to measure DC and / or AC current. The output from the transducer is an analogue current or voltage signal. This can be used as an input to a power analyzerdata acquisition system or meter or control system. Current sensor technologies include current shunts, Rogowski coilsfluxgate sensors (zero flux) and current clamps.

A current sensor is a sensor used for measuring the current flowing in a wire or conductor. Current sensors can be used to measure DC or AC current. The output from the sensor is an analogue current or voltage signal. This can be used as an input to a power analyzer, data acquisition system or meter or control system.

A current clamp is a clamp used for measuring the current flowing in a wire or conductor. Current clamps can be used to measure DC or AC current. The output from the clamp is an analogue current or voltage signal. This can be used as an input to a power analyzer, data acquisition system or meter or control system.

A current sensor is a sensor used to measure the current flowing in a wire or conductor. They are known by several names such as current sensor, current transducer or current clamp. Applications include power measurement and current monitoring on motors, generators, transformers and any electrical installation. A current sensor can be used to measure AC and DC current, depending on the measurement technology.

Once current is supplied through a wire or a conductor, then a voltage drop takes place and a magnetic field will be generated around the current carrying conductor. There are two kinds of current sensing, these are direct current sensing & indirect current sensing. Direct sensing uses Ohm’s law whereas indirect sensing uses Ampere’s & Faraday’s law.

Direct sensing is used to measure the voltage drop associated with the flow of current throughout passive electrical components known as shunt resistors. Direct sensing is used to measure current up to 20ARMS. This is based on Ohm’s law.

Similarly, indirect sensing is used to measure the magnetic field nearby a current-carrying conductor. After that, the magnetic field which is produced is used for inducing proportional current or voltage which is afterward changed to use for measurement or control purposes.

Our current sensor product range consists of fluxgate transducers and Rogowski coil sensors. Zeroflux transducers have the highest accuracy and very high bandwidth, whilst Rogowski coil sensors have excellent accuracy and ultra high bandwidth. Our power analyzers have direct current inputs for current measurement up to 20A RMS.

A current transformer steps the current up or down from its source. It can be used for measuring current, with a lot of turns, for example, 1000 to 1 turns ratio. A current transducer on the other hand directly converts the energy into another type of energy. For example, electric current into a voltage output signal.

  • Flux gate sensors (AC and DC current measurement)
  • Rogowski coils (AC current measurement)
  • Current transformers (AC current measurement)
  • Hall effect sensors (AC and DC current measurement)
  • Current shunts (AC and DC current measurement)

Current sensors can be made using several techniques and each has its own pros and cons. Selection of the current sensor to be used depends on requirements such as magnitude, accuracy, bandwidth, robustness, cost, isolation or size. The user also needs to consider the installation environment.

The accuracy of current sensors is dependent on the technology used with the sensor. The highest accuracy is achieved with fluxgate sensors which have an accuracy of 1ppm. Rogowski coil sensors are calibrated to an accuracy of ±0.2% with the conductor central in the coil. High bandwidth burden resistors have an accuracy of ±0.03% of reading from 0.5 Hz to 1 kHz.

A zero flux transducer uses the flux gate principle. The current to be measured generates a magnetic flux that is counteracted by the flux generated by a secondary winding.

In general terms, the flux gate principle is to use an excited magnetic material coil as a probe. Thanks to a saturation/desaturation cycle and signal processing, this coil is able to measure the magnetic field proportionally. From that multiple options are possible to design a current transducer. It can simply replace a Hall effect probe in the air gap or the coil could have the shape of a tore.

The magnetic field in the toroid generated by the primary current (Ip) is counteracted by the compensating secondary current (Is) generated by the integrator.

The flux gate detects magnetic fields in the toroid from DC to less than 100 Hz at sub ppm levels and tells the integrator to compensate them out.

At higher frequencies, the feedback winding (Nfb) detects magnetic fields in the toroid at ppm levels and tells the integrator to compensate them out as well. The secondary current (Is) is therefore proportional to the primary current (Ip) with the ratio Np:Ns.

In its simplest form a Rogowski coil is an evenly wound coil of N turns per metre on a non-magnetic former of constant cross sectional area A. The winding wire is returned to the starting point along the central axis of the former and the two ends are typically connected to a cable. The free end of the coil is normally inserted into a socket adjacent to the cable connection in a way that allows it to be unplugged thus enabling the coil to be looped around the conductor carrying the current to be measured.

An alternating or pulsed current in a conductor develops a magnetic field and the interaction of this magnetic field and the Rogowski coil local to the field gives rise to an induced voltage within the coil which is proportional to the rate of change of the current being measured. Provided the coil constitutes a closed loop with no discontinuities, it may be shown that the voltage E induced in the coil is proportional to the rate of change of the encircled current I according to the relationship E=H.dI/dt, where H, the coil sensitivity in (Vs/A), is proportional to NA.

To obtain an output voltage VOUT proportional to I it is necessary to integrate the coil voltage E; hence an electronic integrator is used to provide a bandwidth extending down to below 1Hz.

A rotary position sensor, also known as a rotary encoder, is a device used to measure the angular position of a rotating object. It provides feedback regarding the position, speed, and direction of rotation.

There are different types of rotary position sensors, but one common design is an optical encoder. It consists of a light source, a disc with patterns or slots, and a photodetector. As the disc rotates, the light passes through the slots or patterns, and the photodetector converts the light into electrical signals that indicate the position.

There are several types of rotary position sensors, including optical encoders, magnetic encoders, capacitive encoders, and potentiometers. Each type has its own principles of operation and characteristics suitable for different applications.

Rotary position sensors are widely used in various industries and applications. Some common applications include robotics, industrial automation, motor control systems, automotive steering systems, medical devices, and consumer electronics.

Rotary position sensors offer several advantages, such as high accuracy, fast response, durability, compact size, and compatibility with digital interfaces. They can provide precise feedback for controlling systems and enable closed-loop control.

When choosing a rotary position sensor, important factors to consider include the required accuracy, resolution, speed, electrical interface (analog or digital), environmental conditions (temperature, humidity, etc.), mechanical compatibility, and the specific application requirements.

Yes, there are absolute rotary position sensors that can directly measure the absolute position of a rotating object within a full 360-degree range. These sensors typically use multiple tracks or codes to provide unique position values.

Yes, there are multiturn rotary position sensors that can measure position across multiple revolutions or turns. These sensors typically have additional components, such as gears or a multi-track disc, to extend the measuring range beyond a single revolution.

A string potentiometer, or draw wire sensor, is a linear position sensor that measures the displacement or movement of an object. It consists of a retractable wire or string that is attached to the object being measured, and a potentiometer or encoder that converts the linear displacement into an electrical signal.

A string potentiometer works by extending or retracting a wire or string connected to the measured object. As the wire is pulled or released, the position of the object changes, and this change is converted into an electrical signal. The potentiometer or encoder detects the movement and generates an output voltage or digital signal proportional to the displacement.

String potentiometers are commonly used in various applications that require linear position sensing. Some common applications include industrial automation, robotics, machine tools, automotive testing, material handling, and motion control systems.

String potentiometers offer several advantages, including: Non-contact measurement: The wire does not physically touch the potentiometer, reducing wear and tear. Long measuring range: They can measure large linear displacements, typically up to several meters. Compact and lightweight: They are relatively small and lightweight, making them suitable for space-constrained applications. Cost-effective: String potentiometers are often more affordable compared to other linear position sensing technologies.

Yes, some string potentiometers are designed to withstand harsh environments. They may have features such as sealed enclosures or protective coatings to protect against moisture, dust, vibrations, and temperature extremes. It's essential to choose a sensor specifically designed for the environmental conditions of your application.

The installation process may vary depending on the specific sensor and application. Generally, the wire or string should be securely attached to the measured object, and the potentiometer should be mounted in a stable position. Some sensors come with brackets or mounting holes for easy installation. Always refer to the manufacturer's instructions for proper installation guidelines.

Yes, string potentiometers usually provide analog or digital outputs that can be interfaced with a variety of devices and systems. Analog output can be connected to an analog input of a PLC, data acquisition system, or controller. Digital outputs, such as quadrature signals or serial communication protocols, can be used for precise position feedback or integration with a control network.

A Hand Arm Vibration Meter is a device used to measure and assess the levels of vibration transmitted to a person's hands and arms when using vibrating tools or equipment. It helps in evaluating the potential risk of hand-arm vibration syndrome (HAVS) and aids in determining if exposure limits are being exceeded.

A Whole Body Vibration Meter is a device designed to measure and evaluate the levels of vibration experienced by the entire body when sitting or standing on vibrating surfaces or operating vibrating machinery. It assists in assessing the potential health risks associated with prolonged exposure to whole-body vibration.

A Hand Arm Vibration Meter typically consists of an accelerometer sensor that is attached to the hand or arm of a person operating vibrating tools. The sensor measures the accelerations caused by the vibrations and converts it into a vibration magnitude value, usually expressed in meters per second squared (m/s²) or as a vibration exposure value (m/s² A(8)) over a specified period of time. A(8) indicates acceleration exposure over an 8 hour duration.

A Whole Body Vibration Meter typically uses a seat pad and/or a sensor placed at different points on a person's body to measure the vibrations transmitted to the entire body. The sensors detect the accelerations caused by the vibrations and convert them into vibration magnitude values, often expressed as the root mean square (RMS) acceleration in meters per second squared (m/s²) or as a vibration exposure value (m/s² A(8)) over a specific timeframe. A(8) indicates acceleration exposure over an 8 hour duration.

Hand Arm and Whole Body Vibration Meters are used to assess and monitor the level of exposure to vibration in occupational settings. Excessive exposure to vibration can lead to various health issues, including hand-arm vibration syndrome (HAVS), musculoskeletal disorders, circulatory problems, and back pain. These meters help identify potential risks, evaluate compliance with regulations, and implement appropriate control measures.

A piezoelectric pressure sensor is a type of sensor that converts mechanical pressure into an electrical charge or voltage. It utilizes the piezoelectric effect, which refers to the ability of certain materials to generate an electric charge in response to applied mechanical stress.

Piezoelectric pressure sensors consist of a piezoelectric material, typically a crystal or ceramic, sandwiched between two electrodes. When pressure is applied to the sensor, it causes a deformation in the piezoelectric material, generating an electric charge or voltage. This electrical output can be measured and correlated to the applied pressure.

Piezoelectric pressure sensors offer several advantages, including high sensitivity, fast response time, wide measurement range, and ruggedness. They can be used in a variety of environments and are capable of measuring dynamic pressures accurately. Additionally, piezoelectric sensors do not require an external power source for operation.

A pressure sensing element is a device or component used to measure and detect pressire in various applications. It converts mechanical force or pressure into an electrical signal for monitoring, control, or data collection.

Pressure sensing elements typically work based on the principle of deformation or displacement caused by the applied pressure. Common technologies include strain gauges, piezoelectric crystals, capacitive sensors, and resistive sensors. These elements change their electrical properties in response to pressure, allowing for pressure measurement.

Pressure sensing elements are used in a wide range of applications, including industrial automation, automotive systems, medical devices, HVAC (heating, ventilation, and air conditioning), aerospace, and consumer electronics. They are crucial for tasks such as pressure monitoring, control, and safety.

Pressure sensing elements come in various types, including strain gauge-based sensors, piezoelectric sensors, capacitive sensors, and resistive sensors. Each type has its own advantages and is suitable for specific applications.

Absolute pressure sensing elements measure pressure relative to a perfect vacuum, gauge pressure sensors measure pressure relative to atmospheric pressure, and differential pressure sensors measure the difference in pressure between two points. The choice depends on the specific requirements of the application.

Yes, some pressure sensing elements are designed to operate in harsh conditions, such as extreme temperatures, corrosive environments, or high-pressure situations. These sensors are often built with ruggedized materials and protective coatings.

Many modern pressure sensing elements come equipped with digital interfaces like I2C or SPI, making them compatible with microcontrollers and digital communication protocols for easy integration into electronic systems. Remember that the specifics of pressure sensing elements can vary depending on the type and manufacturer, so it's essential to consult the datasheets and documentation provided by the manufacturer for detailed information and guidelines on their use and maintenance.

Inertial navigation is a method of determining the position, orientation, and velocity of an object in motion by measuring the acceleration and angular velocity of the object.

Inertial navigation relies on accelerometers and gyroscopes to continuously measure changes in velocity and orientation. By integrating these measurements over time, it can calculate an object's current position and orientation.

Inertial navigation is used in various applications, including aircraft, spacecraft, submarines, autonomous vehicles, drones and robotics.

Inertial navigation is self-contained and does not rely on external signals, making it reliable in GPS-denied environments. It also provides real-time data and is suitable for high-precision applications.

Inertial navigation systems suffer from cumulative errors, leading to drift in position and orientation estimates over time. To mitigate this, they often need periodic corrections from external references like GPS.

Kalman filters are used to combine measurements from inertial sensors with external references, such as GPS, to improve the accuracy of position and orientation estimates.

Yes, inertial navigation systems are versatile and can be used underwater, in space, and in various challenging environments where other navigation methods may not be reliable.

A gyroscope is a device that measures or maintains orientation and angular velocity. It is used to detect changes in an object's orientation and is a critical component of inertial navigation systems.

Gyroscopes use the principle of angular momentum to measure the rate of rotation or changes in orientation. They are typically based on the conservation of angular momentum.

There are several types of gyroscopes, including mechanical gyroscopes, fiber optic gyroscopes, ring laser gyroscopes, and MEMS (Micro-Electro-Mechanical Systems) gyroscopes.

Gyroscopes have a wide range of applications, including navigation systems for aircraft, ships, and vehicles, as well as in stabilizing cameras, drones, and other devices.

Accelerometers measure linear acceleration, while gyroscopes measure angular velocity. Inertial navigation systems typically use both sensors to determine position and orientation.

Yes, gyroscopes can also suffer from drift, leading to errors in orientation measurement. This drift is one of the challenges that inertial navigation systems must overcome.

Still have questions? Get in touch