Siemens 6SN1123-1AA00-0DA2 Configuration Manual page 370

02.12
05.01
EVALUATE subsystem
The EVALUATE subsystem of the supplementary EMERGENCY STOP safety
function is in this case realized using three SIRIUS 3TK3842 safety relays. The
safety relays have instantaneous and delayed enable circuits.
Safety relay –A1 is used to evaluate the EMERGENCY STOP pushbutton. De-
vices –A2 and –A3 are used to provide a safety–related time delay when swit-
ching off and are controlled from –A1 via the cascading input, terminal 1.
Table 9-17
Safety relays 3TK2842 –A1, –A2 and –A3
PFH
Service life
Performance Level
Result
PFH
Performance Level
RESPOND subsystem
When actuating EMERGENCY STOP, the power supply of line contactor –K2 as
well as contactor relay –K1 are shutdown (de–energized) via the delayed output
(28) from –A1. When requesting EMERGENCY STOP, contactor relays –K3 and
–K4 therefore have no influence on the correct function of –K1 and –K2.
Component –K1 is tested by –A2 via –K3 at each start. Contactor –K2 is tested
by –A1 at each start.
An accumulation of faults in channel 2 between two consecutive actuations of
the EMERGENCY STOP pushbutton is not detected.
S
S
This structure corresponds to Category 3, according to EN ISO 13849–1:2008.
© Siemens AG 2012 All Rights Reserved
SIMODRIVE 611 Configuration Manual (PJU) – 02/2012 Edition
Parameters for the EVALUATE subsystem
Parameter Value
-11
5,4 x 10
d
T1 = 20 years
PLe
-10
1,62 x 10
d
PLe
Basic as well as well–proven safety principles – such as the requirements
regarding Category B – are maintained. Protective circuits are provided.
Protective circuits are provided.
When a component fails, the safety function is always maintained.
The failure is detected.
9 Cabinet Design and EMC
9.4 Application examples
Comment
/h Manufacturer's data
Manufacturer's data
No differences between instantaneous
and delayed enable circuits
/h PFH = PFH (–A1) +PFH
d d
(–A2) + PFH (–A3)
d d
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