Evaluation Of A Power Contactor - Siemens SINAMICS DCM User Manual

Evaluating the safety functions according to EN ISO 13849 when using one switching device
9.3 Evaluation of "Respond"
9.3.1.2

Evaluation of a power contactor

Result, power contactor
Result
PL
PFH
D
Average probability of a dangerous
failure per hour
Determination of the PL, power contactor, channel 1
Parameter
MTTF
D
Power contactor
DC
Measures against CCF
Category
Calculation of the MTTF
D
Parameter
B10
B10 value power contactor
Percentage of dangerous failures
EMERGENCY STOP command
device
d
op
average operating time in days per
year
h
op
average operating time in hours
per day
t
cycle
average time between the start of
two consecutive cycles of the com-
ponent
52
d
1.01 E-07
Value
High
High
Fulfilled
3
for power contactor, channel 1
Value
1 * 10
6
0.73 (73 %)
365 days per year
24 hours per day
24 hours per cycle
Reason
The values for determination are listed in the following ta-
bles.
Reason
MTTF ≥ 30 years (1,563.77 years)
D
DC = 99 %
direct monitoring using mirror contacts
It is assumed that the user has taken the necessary
measures.
One single failure does not result in the loss of the safety
function
Reason
Manufacturers data
Manufacturers data
Assumption:
The device can be actuated
every day of the year
Assumption:
there is one day between
actuating the EMERGENCY
STOP (testing the
EMERGENCY STOP)
Application document for functional safety STO, SS1 (ISO 13849-1)
Compact User Manual, 09/2016, A5E34871844AM
SIEMENS AG
User