An automatic trip is an action performed by some system, usually a
safety instrumented system,
programmable logic controller
A programmable logic controller (PLC) or programmable controller is an industrial computer that has been ruggedized and adapted for the control of manufacturing processes, such as assembly lines, machines, robotic devices, or any activity tha ...
, or
distributed control system, to put an industrial process into a safe state. It is triggered by some parameter going into a pre-determined unsafe state. It is usually preceded by an
alarm to give a process operator a chance to correct the condition to prevent the trip, since trips are usually costly because of lost production.
References
Safety engineering
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