BECKHOFF TwinSAFE - Manual (Page 98)

Circuit examples
96 Application Guide TwinSAFE
EL2904
Parameter Value
Current measurement active Yes
Output test pulses active Yes
2.16.2 Block formation and safety loops
2.16.2.1 Block 1
2.16.3 Calculation
2.16.3.1 PFH / MTTF
d
/B10
d
– values
Component Value
EL1904 – PFH 1.11E-09
EL2904 – PFH 1.25E-09
EL6900 – PFH 1.03E-09
S1 – B10
d
100,000
Light curtain – PFH
d
1,50E-08
MS1 – B10
d
100,000
MS2 – B10
d
100,000
MS3 – B10
d
100,000
MS4 – B10
d
100,000
K1 – B10
d
1,300,000
K2 – B10
d
1,300,000
Days of operation (d
op
) 230
Hours of operation / day (h
op
) 8
Cycle time (minutes) (T
cycle
) 60 (1x per hour)
Lifetime (T1) 20 years = 175200 hours
K1
K2
EL1904 EL6900 EL2904
Light-
curtain
MS
MS
MS
MS
EL1904 S1