The linear measuring MPS Magnetic Position Sensor from Sick is a solution for the analogue querying of piston position on pneumatic cylinders combining flexibility with user-friendliness and precision.
High resolution and accuracy, a variety of housing lengths for differing measurement ranges, as well as suitability for the high velocities of cylinder pistons make the MPS suitable for many applications.
According to the automation task, the MPS series covers measurement ranges of 32 mm, 64 mm, 96 mm or 128 mm. The corresponding differing housing lengths of the MPS are achieved by length-ening the extruded plastic housing profile.
In practical use, the flexibility of this analogue path meas-urement system means that, on the one hand, the T-slots on the cylinder need not be occupied with sensors for individual switching points and, on the other hand, the teach-in function eliminates the need for mechanical sensor adjustment. Zero- and end-point adjustment offers users high resolu-tions for the measurement range.
In order to ensure simple and reliable installation, the housing of the MPS piston position sensor has been designed in such a way that it allows rapid drop-in mounting from above into all common T-slots, and fixing with two screws. The IP67-protected sensor housing contains Hall sensors (for non-contact position detection), the controller and the teach-in element on two circuit boards, amongst others.
The zero- and end-point, i.e. the actual desired measurement range, can be taught-in via the teach button regardless of the piston position and the magnetic field pole. The intermediate piston posi-tions are transmitted as analogue signals that are available as 4 - 20 mA current output and as a 0 - 10 V voltage signal. The querying of piston position takes place at piston speeds of up to 3 m/s and with high precision. The resolution is 0.05 mm, the linearity error is 0.3 mm for any measurement range, and the repeatability accuracy is 0.1 mm.
With the help of MPS, it is possible for a pneumatic drive to achieve a level of accuracy that is suitable for numerous tasks that have hitherto been solved with linear motors. This allows users to deploy pneumatic drives extensively in traditional applications and exploit their features such as speed and economy.
As a result of the four different measurement ranges, the advantages of the MPS are not restricted to ultra-short movement applications with measurement ranges of just a few millimetres, but generally benefit compact cylinder applications with measurement ranges of up to 128 mm. Future device features such as additional programmable switching points or IO Link capability are expected to further improve the range of functions of the MPS and appropriately equipped pneumatic drives.