Aerotech Automation1 iXR3, Hardware Manual

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2.10.1. STO Standards
Table 2-51 describes and specifies the safety requirements at the system level for the Safe Torque
Off (STO) feature of the XSP3-10, -20, -30 and XSL3-10-40 products. This assumes that diagnostic
testing is performed according to
Section 2.10.4. and Table 2-52 .
Table 2-51: STO Standards
Standard Maximum Achievable Safety
EN/IEC 61800-5- 2:2016 SIL 3
EN/IEC 61508-1:2010 SIL 3
EN/IEC 61508-2:2010 SIL 3
EN ISO 13849-1:2015 Category 4, PL e
EN/IEC 62061:2005 with Amendments SIL 3
Table 2-52: STO Standards Data
Standard Value
EN ISO 13849-1:2015
MTTF
D
> 1000 years,
DC
AVG
99%
Maximum PL e, Category 4
EN ISO 13849-1:2015
EN/IEC 61508
Lifetime = 20 years
No proof test required
Interval for manual STO test:
l
Once per year for SIL2/PL d/category 3
l
Once per three months for SIL3/PL e/category 3
l
Once per day for SIL3/PL e/category 4
EN/IEC 61508
SIL3
PFH < 3 FIT
SFF > 99%
iXR3/XR3 Hardware Manual 2.10.1. STO Standards
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