The Generator ECM monitors the output signals from the generator primary speed sensor (1). The function of the primary speed sensor is to find the incremental position of the generator rotor. The generator position and the generator speed signals provide absolute rotor positioning feedback to the Generator ECM. Using the information provided by the generator speed sensor and also information provided by current sensors in the power inverter, the Generator ECM can determine the absolute position of the generator rotor.
The generator secondary speed sensor (2) is a backup sensor if the primary sensor is inoperative. If both generator speed sensors are inoperative the Control 1 section of the power train will not be enabled by the Machine ECM.