A numerical control apparatus includes: a numerical control unit that generates a command position; a drive control unit that is connected to the numerical control unit; and a signal measurement unit that is connected to the numerical control unit and the drive control unit. The drive control unit generates a command controlling a drive unit connected to a control target such that the control target follows the command position, and generates indicator signal data to be output to the numerical control unit and the signal measurement unit. The numerical control unit includes an arithmetic unit that performs processing of acquiring the indicator signal data as first indicator signal data and second indicator signal data, comparing the two indicator signal data, calculating a communication delay of the second indicator signal data with respect to the first indicator signal data, and determining input time of the measured signal.

A sensor system for monitoring a motor that drives a machine arrangement via a rotating motor shaft, wherein a machine cycle is given by a periodic movement pattern of the machine arrangement and/or of the motor shaft, comprises an acceleration sensor for detecting an acceleration of the motor; and an electronic control unit that is in signal connection with the acceleration sensor and that is configured to carry out a comparison of the detected acceleration with at least one predefined threshold value for a wear recognition and to consider the machine cycle in the comparison. The electronic control unit is configured to automatically recognize the machine cycle based on a periodically occurring pattern in the time development of the detected acceleration of the motor.

A numerical control apparatus includes: a numerical control unit that generates a command position; a drive control unit that is connected to the numerical control unit; and a signal measurement unit that is connected to the numerical control unit and the drive control unit. The drive control unit generates a command controlling a drive unit connected to a control target such that the control target follows the command position, and generates indicator signal data to be output to the numerical control unit and the signal measurement unit. The numerical control unit includes an arithmetic unit that performs processing of acquiring the indicator signal data as first indicator signal data and second indicator signal data, comparing the two indicator signal data, calculating a communication delay of the second indicator signal data with respect to the first indicator signal data, and determining input time of the measured signal.