Abstract: A time-based control system (10) for controlling a process incorporating external devices using a predefined response profile (13). The response profile (13) is continuously compared to the actual response of the controlled device (11). A plurality of sensor modules (24) is used to monitor the actual magnitude and direction of change of selected quantities during the process. If the response it outside the user-defined maximum allowable error, appropriate measures are taken to either correct the error, halt the process, or proceed with the process in a time-based mode. The proper response and detection of errors of the controlled device (11) is independent of load, rate, temperature and other external stimuli. The time-based control system (10) can detect errors caused by higher level equipment such as the sensor modules (24). Thus, the time-based control system (10) can detect when any portion of the time-based control system (10) or the controlled device (11) malfunctions.