Siemens 6SN1123-1AA00-0DA2 Configuration Manual page 377

9 Cabinet Design and EMC
9.4 Application examples
Determining DC
Determining
Performance Level
9-376
Table 9-22 Determining the diagnostic coverage level (DC)
Parameter Value
DC (channell 1) 99 %
DC (channel 2) 90 %
93,3 % →
DC
avg
average
S
Structure of the SRP/CS corresponding to Category 3
S
MTTF is average
d
S
DC is average
avg
S
Sufficient measures against common cause failures
Acc. to EN ISO 13849–1:2008 Annex K PLd with PFH
ned.
Note
Contactor relays –K3, –K4 and –K6 should be replaced in plenty of time.
Operating time T = B
10d 10d
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 apply.
This means that in total, the adequate number of 65 points is reached.
SIMODRIVE 611 Configuration Manual (PJU) – 02/2012 Edition
Comment
Testing –K1 (–A11...–A16) via –K3 in the feedback cir-
cuit of –A2, as well as –K6 at –A3 each time the protec-
tive door is closed.
Testing –K2 and –K3 in the feedback circuit of –A1
when EMERGENCY STOP is requested.
Undetected fault accumulation is possible between the
demands.
Testing –K4 in the feedback circuit of –A2 each time the
protective door is closed.
DC
1
MTTF (channel 1)
d
DCavg =
1
MTTF (channel 1)
d
/ n = 2,54 years.
op
© Siemens AG 2012 All Rights Reserved
02.12
05.01
DC
2
+
MTTF (channel 2)
d
1
+
MTTF (channel 2)
d
-7
= 5,5 x 10 / h is attai-
d