This rotational speed sensor monitors the shaft or gear speed within the electrical system of the host machine. It generates a pulsed signal that the control unit uses to manage feed rates, rotor speed, or other time-critical functions in the forage harvester or combine. A failing sensor produces erratic or missing pulses, which can trigger warning codes or cause the machine to enter a reduced operating mode. The manufacturer constructs this sensor to match the original thread and seating depth, ensuring the sensing tip maintains the correct air gap from the target tooth or keyway. When installing, clean the mounting bore and apply thread sealant to prevent fluid ingress.