9
05.01
9.4 Application examples
9-358
©
Siemens AG 2012 All Rights Reserved
SIMODRIVE 611 Configuration Manual (PJU) – 02/2012 Edition
An accumulation of faults between two consecutive actuations of the EMER-
GENCY STOP pushbutton is not detected:
S
Basic as well as well–proven safety principles – such as the requirements
regarding Category B – are maintained. Protective circuits are provided.
S
When a component fails, the safety function is always maintained.
The failure is detected.
This structure corresponds to Category 3, according to EN 13849–1:2008.
Table 9-7
Determining MTTF
d
Parameter
Value
Comment
Channel 1
Safety relay –K1 on the control module
B
10d
value
20.000.000
Manufacturer’s data
n
op
12 pro Jahr
12 actuations per year as a result of
EMERGENCY STOP
MTTF
d
(–K1)
16.666.666 years
→
capped to
100 years
MTTF
d
=
B
10d
0,1 x n
op
Channel 2
Line contactor –K2 in the line infeed
B
10d
value
1.333.333
Manufacturer’s data
n
op
12 pro Jahr
12 actuations per year as a result of
EMERGENCY STOP
MTTF
d
(–K2)
1.111.111 years
→
capped to
100 years
MTTF
d
=
B
10d
0,1 x n
op
Intermediate results, RESPOND (channels 1 and 2)
MTTF
d
(REAGIEREN)
100 Jahre
→
hoch
MTTF
d
values for both channels were capped at
100 years
→
it is not necessary to symmetrize
both channels
Determining
MTTF
d
9 Cabinet Design and EMC
02.12