Festo CMMP-AS M0 Series, Руководство пользователя

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40 Festo — CMMP-AS-...-M0 — 2022-07c
Glossary
9 Glossary
Term/abbreviation Description
CCF Common Cause Failure in accordance with EN ISO 13849-1.
DC avg Average Diagnostic Coverage, diagnostic coverage in accordance with
IEC 61508 and EN 61800-5-2.
FCT Festo Configuration Tool, software for configuration and commissioning.
HFT Hardware Fault Tolerance in accordance with IEC 61508.
Cat. Category in accordance with EN ISO 13849-1, steps 1-4.
MTTF
d
Mean Time To dangerous Failure: time in years until the first dangerous failure
occurs with 100% probability, in accordance with EN ISO 13849-1.
Emergency off In accordance with EN 60204-1: electrical safety is ensured in case of emer-
gency by switching off the electrical power to all or part of the installation.
Emergency off is to be used where a risk of electric shock or other electrical
risk exists.
Emergency stop In accordance with EN 60204-1: functional safety is ensured in an emergency
by bringing a machine or moving parts to standstill.
Emergency stop is intended to stop a process or a movement if this has
created a hazard.
OSSD “Output Signal Switching Device”: output signals with 24 V level cycle rates
for error detection.
PFD Probability of Failure on Demand according to IEC 61508.
PFH Probability of dangerous failures per hour in accordance with IEC 61508.
PL Performance Level in accordance with EN ISO 13849-1: steps a … e.
SFF Safe Failure Fraction [%], ratio of the failure rates of safe and dangerous (but
detectable) failures to the sum of all failures in accordance with IEC 61508.
Safety relay unit Device for execution of safety functions or achievement of a safe status of the
machine by switching off the power supply to dangerous machine functions.
The desired safety function is only achieved in combination with further risk
reduction measures, whereby the shutdown can be a motor controller, for
example.
SIL Safety Integrity Level, discrete levels for determining the safety integrity
requirements of safety functions in accordance with IEC 61508, EN 62061
and EN ISO 13849.
SIL CL SIL claim limit for a subsystem.
STO Safe Torque Off in accordance with EN 61800-5-2.
T Service life in accordance with EN ISO 13849-1.
Tab. 25: Terms and abbreviations