JUMO dTRANS T06 Ex, Руководство по эксплуатации

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6 Safety manual
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Functional unit Unit consisting of hardware or software or both that is suitable for performing a specified
task.
Dangerous failure Failure of an element and/or subsystem, and/or system involved in implementing the safety
function, which
a) prevents the safety function being executed on demand (on-demand operation type), or
causes the failure of a safety function (operation with continuous demand), so that the
EUC transitions to a dangerous or potentially dangerous state; or
b) reduces the probability of executing the safety function correctly on demand.
Safe failure Failure of an element and/or subsystem, and/or system involved in implementing the safety
function, which
a) causes false triggering of the safety function, switching the EUC (or parts of it) to a safe
state, or maintaining a safe state; or
a) increases the probability of false triggering of the safety function, switching the EUC (or
parts of it) to a safe state, or maintaining a safe state.
Hazard Potential source of damage
Safety Freedom from unreasonable risk
Safety function A function that is performed by an E/E/PE safety-related system, safety-related system
based on other technology, or external equipment for reducing risk with the goal of
achieving or maintaining a safe state for the EUC taking into consideration a specified
dangerous event
Safety integrity The probability of a safety-related system performing the required safety function under all
specified conditions within a specified period of time according to requirements.
Safety Integrity Level (SIL) One of four discrete levels for specifying the requirement for safety integrity of the safety
functions assigned to the E/E/PE safety-related system. Safety integrity level 4 represents
the highest level of safety integrity, while safety integrity level 1 represents the lowest.
Name Description