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Entry type: FAQ, Entry ID: 77284316, Entry date: 11/21/2017

SIRIUS Safety Integrated: Safe speed monitoring, protective door monitoring and tumbler monitoring to SIL 3 or PL e with a speed monitor

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The speed monitor ensures that no access is permitted to the moving, dangerous machine parts above an adjustable speed. 


A safe speed window is set on the speed monitor. As long as the speed is outside this safe speed window, access to the moving, dangerous machine parts is prevented by a protective door with a tumbler. At the same time, the speed monitor monitors the position of the protective door.
You can change between setup mode and automatic with individual speed windows using a mode switch. A detected standstill and observance of the set speed window are output via two relay outputs

In automatic mode, the protective door remains locked as long as no standstill is detected. If the automatic speed window is overshot or undershot, the power contactors are switched off in a safety-related manner. In setup mode, the protective door is permanently enabled. If the setup speed window is overshot or undershot, the power contactors are switched off.

If the protective door is open, the speed monitor ensures that the motor cannot be switched on. If the door is closed and the feedback circuit is closed, the Start button can be used to switch on again.



Content of Downloads


Wiring diagrams   Speed_monitoring_Interlocking_SIL3_3TK28_wiring.zip ( 3778 KB )
Project for Safety Evaluation Tool Speed_monitoring_and_Interlocking_SIL3_3TK28_set.zip ( 29 KB )


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Hardware platform:  Safety, SIRIUS
Software:  none
Entry contens:  Application Examples

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