Iso 13849-1 - Siemens SINUMERIK 840D sl Function Manual

2.2.4 EN ISO 13849-1
EN ISO 13849-1 is based on previous standard EN 954-1, and additionally requires a
quantitative consideration of the safety functions. The following safety-related parameters are
required for components/devices:
● Category (structural requirement)
● PL:
● MTTF
● DC:
● CCF:
The standard describes how the Performance Level (PL) is calculated for safety-related
components of the controller on the basis of designated architectures. In the event of any
deviations from this, EN ISO 13849-1 refers to EN 61508.
When combining several safety-related parts to form a complete system, the standard explains
how to determine the resulting PL.
2.2.5 EN 62061
EN 62061 (this is identical to IEC 62061) is a sector-specific standard below EN 61508. It
describes the implementation of safety-related electrical control systems of machines and
takes into account the complete lifecycle - from the conceptual phase to de-commissioning.
The standard is based on the quantitative and qualitative analyses of safety functions.
The standard systematically applies a top-down approach to implementing complex control
systems (known as "functional decomposition"). The safety functions derived from the risk
analysis are sub-divided into sub-safety functions, which are then assigned to real devices,
sub-systems, and sub-system elements. Both the hardware and software are covered. EN
62061 also describes the requirements placed on implementing application programs.
A safety-related control systems comprises different subsystems. From a safety perspective,
the sub-systems are described by means of the characteristic quantities (SIL claim limit and
PFH
Programmable electronic devices, e.g. PLCs or variable-speed drives must comply with EN
61508. They can then be integrated into the control system as subsystems. The following
safety-related characteristic quantities must be specified by the manufacturers of these
devices.
Safety Integrated
Function Manual, 12/2017, 6FC5397-4BP40-6BA1
Performance Level
: Mean Time To dangerous Failure
d
mean time to dangerous failure
Diagnostics coverage
Diagnostic coverage
Common Cause Fault
Common Cause Failure
).
D
Regulations and standards
2.2 Machine safety in Europe
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