The invention relates to a lubricating device that includes a lubricant pump, a lubricant reservoir for supplying lubricant to a machine to be lubricated, a control unit for determining an operating state of a machine and for operating the lubricant pump based on the signals of at least one sensor configured to detect emissions emanating from the machine to be lubricated, and a housing configured to be attached to a lubrication nozzle of the machine to be monitored. It is proposed that a reading of the signals of the sensor by the control unit is limited to a predetermined set of time windows with a predetermined width, wherein the time windows are separated by an interval where the signals of the sensor are not read.