9
05.01
9.4 Application examples
9-371
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Siemens AG 2012 All Rights Reserved
SIMODRIVE 611 Configuration Manual (PJU) – 02/2012 Edition
Table 9-19
Determining the diagnostic coverage level (DC)
Parameter
Value
Comment
DC (channel 1)
99 %
Testing –K1 via –K3 in the feedback circuit of
–A1
DC (channel 2)
99 %
Testing –K2 in the feedback circuit of –A1 when
EMERGENCY STOP is requested
DC
avg
99 %
→
high
DC
avg
= DC (channel 1) = DC (channel 2)
S
Structure of the SRP/CS corresponding to Category 3
S
MTTF
d
is high
S
DC
avg
is high
S
sufficient measures against common cause failures
Acc. to EN ISO 13849–1:2008 Annex K, PLe mit PFH
d
= 4,29 x 10
-8
/ h is
attained.
Measures against common cause failures CCF of the
safety function
According to EN ISO 13849–1 Annex F, for SRP/CS from Category 2, a mini-
mum of 65 points is required.
The considerations according to Chapter 9.4.1 Table 9-9.
This means that in total, the adequate number of 65 points is reached.
Checking the PFH value of the complete safety func-
tion
Table 9-20
PFH value of the complete safety function
Parameter
PFH value
PL
Comment
SENSE
4,29 x 10
-8
/ h
e
EMERGENCY STOP pushbutton –S3
EVALUATE
3 x 5,4 x 10
-11
/ h
e
Safety relays –A1, –A2 and –A3
RESPOND
4,29 x 10
-8
/ h
e
Switching elements –K1 and –K2, –K6 and
–K5
Total
8,6 x 10
-8
/ h
e
<1 x 10
-6
/ h
As a consequence, the requirements regarding PLd with Category 3 for the pro-
tective door safety function are fulfilled.
Determining DC
Determining the
Performance Level
9 Cabinet Design and EMC
02.12