Hiwin D1-N Series - Page 67

D1-N Series Servo Drive User Manual Wiring
HIWIN MIKROSYSTEM Corp. 4-27
MD17UE01-1906
B. Timing diagram of deactivating STO safety function
Figure 4.8.8
(4) Maintenance plan
According to IEC 61508 (High demand mode), the minimum maintenance interval of STO safety
function is one year. Table 4.8.4 is provided for your maintenance plan and safety calculation.
Table 4.8.4
Item
Unit
Value
Lifetime of STO Safety Function (IEC 61508) Years 20
Safe Failure Fraction, SFF (IEC 61508) % 99.7
Hardware Fault Tolerance, HFT (IEC 61508) Type A Subsystem 1
Safety Integrity Level, SIL
IEC 61508: 2010
IEC 62061: 2010
SIL3
SILcl3
Performance Level, PL
(ISO 1384: 2008)
e (Category 3)
Mean Time to Dangerous Failure, MTTFD (ISO 13849-1) Years
1606 (After further
calculation, the maximum
value is limited to 100
years)
Diagnostic Coverage, DC (ISO 13849-1) % 99
Probability of Dangerous Failure per Hour, PFH
d
(IEC 62061) 1/h 1.6 X 10
(-9)