Abstract: A power measuring device is disclosed featuring the capability of converting resistively coupled load current and voltage signals to a digital pulse train whose frequency is proportional to the instantaneous power drawn. The digital pulse train can be optically coupled to a microcomputer-based display or process controller for conversion of the pulse train frequency to a power consumption indicating signal.

Abstract: The controller includes a power sensing device which monitors the instantaneous power drawn by the machine and compares it with a predetermined limit level of desired power consumption. A user programmable timer is manually accessible for loading a selected time delay period therein. The controller provides an output capable of altering the machine operation when the machine power consumption has continuously exceeded the limit value for the selected time period. The controller outputs may be latched or nonlatched once an overlimit condition is detected in accordance with a user selectable programmed parameter. In an adaptive mode, the controller forces the feed rate to a programmable feed rate for a selected period of time upon initial impact between the workpiece and the machine tool.