Siemens Simovert Masterdrives Compendium page 65

12.2010
Subsystem
EVALUATE
Parameter
Safety switching devices 3TK2828 -A2
PFH d
Service life
Instantaneous enabling circuits
Performance Level
Time-delayed enabling circuits
Performance Level
Result
PFH d
Performance Level
Subsystem REACT
Siemens AG 6SE7087-6QX70 (Version AM)
SIMOVERT MASTERDRIVES
In this example, the subsystem EVALUATE is provided by a SIRIUS
3TK3828 safety switching device. The safety switching device features
instantaneous and time-delayed electromechanical enabling circuits.
Value
2.7 x 10 -9 / h
T1 = 20 years
PLe
PLd
2.7 x 10 -9 / h
PLd
The subsystem REACT is formed by two channels. The first channel
consists of the safety relay –K1. The second channel consists of the
line contactor –K2 and the contactor relay –K3. Both channels are de-
energized simultaneously by safety switching device –A1 during an
Emergency Stop.
In this example, the subsystem REACT is formed by two channels with
different request rates for each channel. A dangerous fault in channel 1
causes an instantaneous request from channel 2.
The components -K1 and –K3 are tested every time –A1 or
–A2 starts. The contactor –K2 is tested every time –A1 starts.
Accumulation of faults in channel 2 between two consecutive actuations
of the Emergency Stop button is not detected.
♦ The structure conforms to fundamental and proven safety principles
and the requirements of Category B. Protective circuits are
provided.
♦ The safety function always remains operative when a component
fails. Component failure is detected.
This structure corresponds to Category 3 in accordance with EN ISO
13849-1:2008 /R3/.
Compendium Motion Control
Configuration and Connection Examples
Comment
Specified by manufacturer
Specified by manufacturer
with Category 4
with Category 3
= −
PFHd PFHd ( A ) 2
with Category 3
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