turck TBIP-L-FDIO1-2IOL Series, Руководство по безопасности

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V01.0 | 2017/10
10 Appendix: Designations and Abbreviations
Abbreviation Meaning
DC Diagnostic Coverage
E/E/PE-system Electrical/electronic/programmable electronic system
HFT
Hardware failure tolerance
MTTF
D
Mean Time To Failure Dangerous
PFD Probability of dangerous failure on demand
PFH
D
Average frequency of dangerous failure per hour
PL Performance Level
SIL Safety Integrity Level
11 Appendix: Function Tests
Ensure that the function test is only carried out by qualified personnel.
A suggested function test consists of the following steps:
Step Action
1 Switch every safety related input at least once a year.
2 Control the switching behavior by monitoring the output circuits.
3 Observe the maximum duty cycle and the total operation time depending on the select-
ed PFD value.
4 If the maximum duty cycle is reached: Request the shutdown function in order to check
the function of the safety system.
Once the test has been completed, document and archive the results.
12 Appendix: Document History
Version Date Modifications
1.0 2017-10-27 First version