Abstract: In order to oversee and plan, at overall shop level, the execution of maintenance work on several installations (1), each having monitoring equipment (3) which monitors the intervals at which maintenance should be carried out on the installations, it is proposed that the outputs (A.sub.3) from the monitoring equipment (3) be fed to a processing unit (27) which produces maintenance status reports (53) for the whole shop. Registers, which store certain maintenance intervals, are reset only upon recognition of maintenance personnel at the site of the installation by manual input and recognition of the condition at the processing unit by a remote input.

Abstract: A system is described for indicating the appropriate time to perform preventive maintenance operations upon a machine tool. The system includes a signal generator which is to be connected to the machine tool to generate signals whenever the tool is in operation. These signals are integrated and a threshold sensitive detector responsive to the output of the integrator produces a control signal. The control signal is then applied to a audio/visual indicating means to notify operators of the advent of a particular preventive maintenance operation to be performed upon the machine tool.