Consistency Transmitter

The consistency blade type transmitter measures consistency by sensing the "shear force" on a static blade in the stock stream. The size and shape of the blade is designed to compensate for small flow variations. This gives higher accuracy than traditional linear response curves because it adjusts for higher sensitivity at low consistency and lower sensitivity at higher consistency. This force causes the sensor blade to pivot; the amount of movement is proportional to the force needed to separate "shear" the fibers. The sensor blade is connected to a differential capacitor system. This non-contact device measures the movement and produces a variable voltage that is proportional to consistency. Thus "shear force" is converted into a voltage. This voltage is fed into a PID module. The module converts the voltage into a 4-20 mA signal. By utilizing a look up table, the nonlinear consistency sensor voltage is converted to a linear 4-20ma output. The module communicates via protocol on the 4-20 ma signal wires. Span, upper & lower range values and other variables can be adjusted using a standard hand held communicator.