... upward in the tube,the float moves upward to a certain position where the lifting force and ... moves up and down ,it transmits its positional to the indicator outside in form of magnetic-coupling,so ... the float,and by using the cam board to show the value of flowrate linearly on the ... :tow-wire channel 12VDC-36VDC 6.Alarm switch:Solid-state relay,electric current 200mA,voltage 50V 7.Explosin-proof mark ...