Din En Iso 13849-1 (Replaces En 954-1) - Siemens Sinamics S120 Function Manual

10.2.4

DIN EN ISO 13849-1 (replaces EN 954-1)

A qualitative analysis according to DIN EN 13849-1 is not sufficient for modern control
systems due to their technology. Among other things, DIN EN ISO 13849-1 does not take
into account time behavior (e.g. test interval and/or cyclic test, lifetime). This results in the
probabilistic approach in DIN EN ISO 13849-1 (probability of failure per unit time).
DIN EN ISO 13849-1 is based on the known categories of EN 954-1. It now also takes into
account complete safety functions and all the devices required to execute these. With DIN
EN ISO 13849-1, safety functions are investigated from a quantitative perspective going
beyond the qualitative basis of EN 954-1. Performance levels (PL), which are based on the
categories, are used. The following safety-related characteristic quantities are required for
devices/equipment:
● Category (structural requirement)
● PL: Performance level
● MTTF
● DC: Diagnostic coverage
● CCF:
Common cause failure
The standard describes how the performance level (PL) is calculated for safety-related
components of the controller on the basis of designated architectures. For deviations from
this, DIN EN ISO 13849-1 refers to IEC 61508.
When combining several safety-related parts to form a complete system, the standard
explains how to determine the resulting PL.
Not e
DIN E N IS O 13849-1 and machinery directive
Since May 2007, DIN EN ISO 13849-1 has been harmonized as part of the Machinery
Directive.
Safety Integrated
Function Manual, (FHS), 07/2016, 6SL3097-4AR00-0BP6
: Mean time to dangerous failure
d
Standards and regulations
10.2 Safety of machinery in Europe
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