107
2018/02
TBPN-L1-FDIO1-2IOL- Sichere I/O-Kanäle
12 Glossary of terms
DC
Diagnostic Coverage
HFT
The HFT (Hardware fault tolerance) defines
the fault tolerance of a subsystem. The fault tolerance is the capability
of a subsystem to perform a desired function even after an error has occurred.
MTTFd
Mean Time To Dangerous Failure
PFH
DIN IEC 61508-4:2010, Functional safety of electrical/electronic/programmable electronic safety-related systems
- Part
4:
"Average frequency of a dangerous failur
e per hour: Average frequency of a dangerous failure of an E/E/PE safety-
related system, to be able to perform the specified safety function over a given period of time."
PL
A measure of the dependability of the safety function,
according to EN ISO13849-1:2008: Safety-related parts of control systems:
Discrete level used to specify
the ability of safety-related parts of control systems to perform a safety function
under foreseeable conditions.
SIL
Safety Integrity Level
DIN IEC 61508-4:2010, Functional safety of electrical/electronic/programmable electronic safety-related systems
- Part
4:
"Discrete level (one out of a possible four), corresponding to a
range of safety integrity values, where safety integ-
rity level 4 has the highest level of
safety integrity and safety integrity level 1 he lowest."
SIL CL
SIL Claim Limit
Maximum SIL for a subsystem The subsystem is a system with a
defined systematic safety integrity.
To Next Page
Loading...
Need help?
General
