schmersal PSC1 Series Installation Manual page 38

Installation manual
Characteristic data:
Max. achievable safety class
System structure
Design of the operating mode
Probability of a dangerous failure per hour
(PFH value)
Proof test interval (EN61508)
Safety instructions:
•
You will find the specific safety-related characteristic data for the related modules in the tech.
characteristic data in section 3.
•
On the usage of several sensors with different functions (e.g. access door position indication +
speed acquisition) for a safety function (e.g. safely limited speed with access door open), these
are to be considered as connected in series for the safety-related assessment of the overall
system. On this topic see example calculation in the appendix.
•
The safety regulations and EMC directives must be followed.
•
In relation to the fault exclusions assumed, reference is made to the tables in D in the annex of
EN ISO 13849-2.
•
For the safety-related assessment of overall systems, the characteristic data stated in section 3
can be used for the PES sub-system (e.g. PL e and PFH value according to table for verification
as per EN ISO 13849)
The examples shown in the following and their characteristic architecture are definitive for the
allocation to a category according to EN ISO 13849-1.
The resulting maximum possible performance levels according to EN ISO 13849 are also dependent
on the following external component factors:
•
Structure (single or redundant)
•
Detection of common cause failures (CCF)
•
Diagnostic coverage on demand (DC
•
Mean time to the dangerous failure of a channel (MTTF
PSC1-C-10 Installation manual V2.7
Version: 57E
•
SIL 3 as per EN61508
•
Category 4 as per EN954-1
•
Performance Level e as per EN ISO 13849-1
2-channel with diagnostics (1002) according to EN
61508
Architecture category 4 according to EN ISO 13849
"High demand" as per EN 61508
Specific values as per tables "Safety-related
characteristic data"
20 years, after that the module must be replaced
)
avg
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D
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