Data Related To Safety Standards - ABB ACS355 User Manual

404 Appendix: Safe torque off (STO)

Data related to safety standards

IEC 61508
SIL 3
PFH 6.48E-09
(6.48 FIT)
HFT 1
SFF 91%
Abbreviations
Abbreviation
CCF EN/ISO 13849-1
DCavg EN/ISO 13849-1
FIT
HFT IEC 61508
MTTFd EN/ISO 13849-1
PFHd IEC 61508
PL EN/ISO 13849-1
SFF IEC 61508
SIL IEC 61508
STO EN 61800-5-2
Maintenance
Test the operation and reaction of the STO function every year.
EN/ISO 13849-1
PL e
Category 3
MTTFd 470 years
DCavg 18%
Reference
Common Cause Failure (%)
Diagnostic Coverage Average
Failure In Time: 1E-9 hours
Hardware Fault Tolerance
Mean Time To dangerous Failure: (The total number of
life units) / (the number of dangerous, undetected
failures) during a particular measurement interval under
stated conditions
Probability of Dangerous Failures per Hour
Performance Level: Corresponds SIL, Levels a-e
Safe Failure Fraction (%)
Safety Integrity Level
Safe Torque Off
IEC 62061
SILCL 3
Description