The powder material fall into the weighting scale through the transformation buffer, under the action of the prefeed device (such as rotor feeder, single/double screw feeder, two-position/three-in-one flow control valve and rotary unloader). After the powder fall into the rotor scale cylinder, the rotor impeller will scrap the material awary from the feeding mouth, rotate a certain angle, and sent to the discharge hole. Finally the material flow out the rotor scale cylinder by gravity or micro negative pressure and be send to auxiliary conveying equipment at a lower level of service.

The weighting of the rotor scale is realized through Lever balancing mechanism

Which consist of two groups of cross reed (or bearing) and load sensor.

Under the model of weight control, the instrument got the Instantaneous flow through integrating

caculating the weight signal and speed signal, and then compared with the setting flow, and do adjustment through the PID, make "instant traffic" infinite approximation the "set flow", the flow if the system is controlled through the D/A of instrument to output control the operating frequency of vector converter (or the opening of the regulating valve). 

Under the model of volumetric control, the meter calculates the instantaneous flow rate by detecting the natural parameters of the feed machine speed pulse signal system, and then compares and controls it.