The secure safety gate system PSENmlock provides safe interlocking and safe guard locking for personnel and process protection up to safety category PL e. The safe guard locking is enabled by the two-channel control of the guard locking. That makes the switch suitable for machines with dangerous overruns in which guard locking up to PL d or PL e is necessary. Another version is available for series connection. When combined with safety device diagnostics (SDD), individual switches or doors can be controlled separately, without separate wiring in the control cabinet. The SDD also allows simple and extensive safety switch diagnostics, reducing downtime.