Installation of a motion sensor in each lifting jack to check the thrust; Consists of displacement sensor housing, magnetic ring and transition head of three parts. The technical parameters are as follows: Explosion protection type: mine physical safety type Housing protection class: IP68 Working voltage: DC12V Working current: 5 mA Analog output: 0.2 - 1 mA Route range: 0 - 1200 mm Resolution: 0.5% (FS) Temperature range: from -20°C to 60°C Number of units: 1 unit / 1 unit