Haake Trapped-Key Interlocking System HST

Safety of Machineryhst1

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Hazardous machines and systems are frequently equipped with safety elements (safety doors) with a locking mechanism to protect the operator. Their function is: a) to prevent hazardous machine functions if the safety door is not closed and locked, b) to keep the safety door closed and locked until the risk of injury has passed.

A general example: A machine has one or more maintenance openings (part-body access) or is accessible through one or more doors (full-body access). On the one hand, it has to be secured that the machine is switched off, before one of these openings or doors can be opened.

…On the other hand, the machine must only be re-set into operation, if all openings and doors are closed, and nobody is present inside the machine.