New sensors can provide precise position measurement under extreme conditions
Megatron has launched its new RWC series of inductive LVDT displacement sensors, this time in a slim Ø 20.6 mm design, for contactless and wear-free usage. This is possible due to the robust cable connection with IP68 protection. Cables are able to operate underwater and at pressures of up to 30 bar.
Operational uses range from 25mm to 400mm and linearity up to 0.1%, and temperatures range from -40°C to +100°C, with special versions being able to operate up to 200°C and 210 bar.
Using the induction principle, where the movement of the push rod within the coils encapsulates the sensor's housing and generates an electrical output signal analogue to the displacement. There is no wear on the sensor as the push rod is mechanically separated from the coils.
Three variants are available for the new displacement sensor. The first version has a guided push rod and PTFE bearings, which can be screwed together at the end with ball joints, ensuring optimum alignment of the RWC to the measurement object.
A second option features an internal return spring to allow the RWC to be used as a ‘probe’ to measure the distance to an object without a fixed mechanical coupling. The push rod is returned by the built-in spring to its original position when the target moves away.
Finally, the loose rod version attaches directly to the object being measured, such as a piston or fixture. To give an accurate displacement measurement, it must be ensured that the plunger can move exactly in the coils of the LVDT without tilting.
Robust stainless steel cases house the RWC series, allowing them to be used in harsh environments and even underwater. AC power is supplied via a long cable away from the transducer, allowing it to operate.
Other applications include monitoring the position or gap of structures such as bridges, railway tracks, agricultural machinery, and production facilities.
