Embedded coil technology radically improves temperature stability and miniaturisation of displacement sensors


Micro-Epsilon’s new Embedded Coil Technology (ECT) represents a technological breakthrough in eddy current sensor design and manufacture, enabling the previous limitations of using eddy current sensors to be overcome. Due to its ultra-compact design and by using new inorganic materials in its construction, the new eddyNCDT ECT sensors provide almost unlimited scope in terms of the external design and geometrical shape of the sensor. This means the sensors can be adapted to suit virtually any application requirements.

EddyNCDT ECT sensors offer extreme mechanical robustness, resulting in longer service intervals and higher temperature stability. In addition, the complete circuit electronics can now be integrated into the sensor itself, providing an even more compact measurement solution for OEMs and machine builders. The sensors are also suitable for harsh operating environments, including high vibration, impact shocks and high operating temperatures as high as 350 deg C.

Sensors have been produced with extremely low thermal drift and with temperature errors of less than 20ppm/K (parts per million per degree Kelvin).

Chris Jones, Managing Director at Micro-Epsilon (UK) Ltd comments: “Embedded coil technology has enabled us to produce custom-specific designs for OEMs. ECT eddy current sensors are already being used in a variety of applications, including the alignment of mirror segments on giant reflector telescopes; for use in ultra-high vacuums or clean rooms in semiconductor manufacturing; and for measuring the grinding gap on refiners used in paper mills. We are also developing specific solutions for the aerospace and defence sector.”

“Using our electronics expertise from within the Micro-Epsilon Group, we were able to develop extremely compact electrical circuits, which allowed us to manufacture the sensor with integrated electronics in the sensor head. We are therefore able to produce a single or multiple sensor channel arrangement in one sensor body,” he adds.

Custom capacitive sensors

As well as eddy current sensors, Micro-Epsilon has also designed capacitive displacement sensors that make use of ECT. The capaNCDT ECT sensors are manufactured using a new type of production process. Similar to the eddy current ECT method, by embedding the electronic components in an extremely stable carrier material, significantly better temperature stability can be achieved compared to conventional capacitive displacement sensors.

CapaNCDT ECT sensors can withstand operating temperatures as high as 200 deg C, as well as very low temperatures down to –269 deg C. Similar to eddyNCDT ECT sensors, the capacitive versions are extremely compact. Micro-Epsilon’s capaNCDT CSH-FL, for example, has an installation height of just 4mm.

For more information on Micro-Epsilon’s ECT eddyNCDT and capaNCDT ECT displacement sensors, please call the sales department on 0151 355 6070 or email: info@micro-epsilon.co.uk