Increase safety and productivity of packaging machines with the modular Safeguard Detector safety sensor. The Safeguard Detector consists of two MultiPulse photoelectric proximity sensors, and the Flexi Soft safety controller or the UE410-SD safety evaluation module. Safeguard Detector safely detects whether a movable physical guard is located at a previously defined position, e.g., the packaging material in the carton magazine of packaging machines. If there is sufficient packaging in the carton magazine, then it is not possible to reach into the hazardous area while the machine is running.