Free guide to eddy current displacement sensors

With what is claimed to be the widest choice of custom and standard eddy current sensors in the world today, Micro-Epsilon has now brought together the 28 most common variants of its eddyNCDT sensor range and detailed them in an easy-to-use reference guide.

Eddy current displacement sensors measure distances, displacements or the position of any electrically conductive target. Micro-Epsilon's eddyNCDT range offers a number of advantages for the user, including very stable measurements, high resolution and linearity, excellent temperature range and stability, high measurement rates and sealing to IP67. Micro-Epsilon claims that a unique feature of the eddyNCDT range is the patented "active temperature compensation' and field calibration capability.

The company says its eddyNCDT 3300 is suitable for harsh ambient conditions or where maximum precision is required. Various sensor models are available to cater for all application requirements. For example, the miniature eddyNCDT range uses variable coil geometry and innovative production technologies in order to offer customers a sensor that has installation dimensions of less than 2mm.

Pressure-resistant versions are available up to 2000bar. Operating temperatures are from -50 up to 235degC and robust IP67 versions are also available. An active sensor, controller and cable compensate for temperature fluctuations, offering extreme temperature stability of 0.015 per cent per degree C. Measurement ranges are from 0.4-80mm, linearity is 0.2 per cent and resolution is 0.01 per cent of the measurement.

The eddyNCDT 3300 measurement system consists of a sensor, sensor cable and a controller with adapter board. This design means it is possible for users to operate all eddyNCDT sensors with only one controller. The adapter board represents the link between sensor, cable and the electronics. The sensor type used, cable length and target material are stored on this board. It adapts the various sensors to the oscillator and demodulator standard circuits and also contains the settings for temperature compensation. When changing or replacing a sensor, only the sensor, sensor cable and adapter board need to be replaced. The adapter board also enables the user to easily adapt the sensor for different applications, for example, if the target material, size or shape changes.

Multi-channel control platform

A new controller is now available that enables users to synchronise the system for multi-channel applications. The MCT304 multi-channel platform is available for thickness and displacement measurements with up to four channels. Up to four controllers can be integrated in a single MCT platform. The platforms can be synchronised with each other, whereby the simultaneous operation of any number of eddyNCDT sensors is possible. In order to compensate for opposing sensor influences, the systems are synchronised by means of a master/slave synchronisation cables.

Potential applications for the eddyNCDT 3300 include automotive inspection systems, tensile strength testing in steelworks, measuring the thickness of foil, compressor/turbine gap, shaft displacement and edge control. The miniature sensors are used extensively in automotive research and development. Applications include measurement of valve stroke, injection needle movement, cylinder head breathing, lubricating gap, oil film thickness, crankshaft concentricity and axial movement of the crankshaft.

Follow the link for more information about Micro-Epsilon's range of eddy current displacement sensors.

To request a free copy of the guide, email [email protected].