FSB30 series analog type flow switch uses mechanical measurements, whose measurement range is wide, and easy to
adjust. With the alarm, it also equippes a pointer dial which can intuitively display the current velocity of the flow,
it is a multi-function measuring instrument with both display ability and the control ability.
FSB31 is all mechanical measuring, stable and reliable. It uses a wide range, and the optional diameter is
DN15 to~DN300, the installation can choose thread, flange and insertion methods and so on. If there is not welding
joint when measuring, we suggest you to choose easy welding joint, the dimensions and parameters can be seen
in part description.

The principle of FSB30 series analog baffle-type is described as following: The flow switch is installed in the central of the pipe.
        When the fluid flow in the pipe, through the effect by flowing fluid, the shaft will overcome the preload which is on the
        adjusting spring and deflect a certain angle, the touching screw in the shaft will deflect and leave the preloading micro
        switch, and the micro switch will back to normal (the normally open contact is cut, the normally close contact is
        closed), at this time if it sends normal signal, it mean there is fluid flowing in the pipe. The deflection of the shaft drive
        the pointer deflecting, and you can read the velocity on the dial directly. When the velocity in the pipe becomes smaller,
        the force on the baffle by the flowing liquid becomes small, too, and the shaft will rotate on the elasticity of the adjusted
spring, the shaft will drive the touching screw outskirting the micro switch. When the velocity reduced to less than the
flow switch’s setting acted velocity, the touching screw will make the micro switch sending an alarm signal, means that
the velocity of the flow in the pipe is less than the setting value.