Abstract: A control for a web processing machine such as for a printing press is described for detecting web breaks, faulty web sensors and inconsistent web threading conditions. A logic network is employed to compare web sensor signals with control signals to detect whether the web sensor signals are consistent with what is called for by associated control signals. Station status signals are produced to stop the machine when inconsistent conditions are sensed and cause appropriate web severing. A bypass control network is provided to inhibit the station status signals for slow speed checkout. However, when the machine speed exceeds a predetermined level, the bypass network is automatically deactivated and full machine control protection restored.