ABB ACQ580-07, Hardware Manual

Page: 292 / 324

Safety data
The safety data for the Safe torque off function is given below.
Note: The safety data is calculated for redundant use, and does not apply if both STO
channels are not used.
TM
(a)
CCF HFT SC Cat.
DC
(%)
MTTFD
(a)
PFDavg
(T1 = 5
a)
PFDavg
(T1 = 2
a)
PFH
(T1 =
20 a)
(1/h)
SFF
(%)
PL
SIL/
SILCL
Frame
size
20 80 1 3 3 ≥90 9380
8.59E-
05
3.44E-
05
3.92E-
09
>99 e 3
R6
R7
20 80 1 3 3 ≥90 8792
9.24E-
05
3.69E-
05
4.22E-
09
>99 e 3
R8
R9
20 80 1 3 3 ≥90 15080
9.14E-
05
3.66E-
05
4.18E-
09
99.55 e 3
R10
R11
3AXD10000015777 N, 3AXD10000410558 F
• The following temperature profile is used in safety value calculations:
• 670 on/off cycles per year with Δ T = 71.66 °C
• 1340 on/off cycles per year with Δ T = 61.66 °C
• 30 on/off cycles per year with Δ T = 10.0 °C
• 32 °C board temperature at 2.0% of time
• 60 °C board temperature at 1.5% of time
• 85 °C board temperature at 2.3% of time.
• Relevant failure modes:
• The STO trips spuriously (safe failure)
• The STO does not activate when requested
• A fault exclusion on the failure mode “short circuit on printed circuit board” has
been made (EN 13849-2, table D.5). The analysis is based on an assumption
that one failure occurs at one time. No accumulated failures have been analyzed.
• STO response times:
• STO reaction time (shortest detectable break): 1 ms
• STO response time: 2 ms (typical), 5 ms (maximum)
• Fault detection time: Channels in different states for longer than 200 ms
• Fault reaction time: Fault detection time + 10 ms
• Indication delays:
288 The Safe torque off function