Operating Instructions - VEGAPULS 54K enamel

24 101-EN-041227
Supplement
6 Safety-related characteristics
The failure rate of the electronics and the antenna system was determined by an FMEDA (Failure
Mode, Effects and Diagnostics Analysis) acc. to IEC 61508. The number values are based
on an output current tolerance of max. 2 %.
Architecture 1oo1D SIL 2
VEGAPULS 51
VEGAPULS 52
VEGAPULS 53
Overfill protection Dry run protection Individual level
VEGAPULS 54
VEGAPULS 56
Max
HFT 0
SFF > 86%
PFD avg 1) < 0.12 10 -2 bei T Proof = 1 Jahr 2)
< 0.60 10 -2 bei T Proof = 5 Jahre
PFH [1/h] 3) < 0.28 10 -6
Failure reaction time T Reaction = 60 sec
PFDavg
0,60·10 -2
0,48·10 -2
0,36·10 -2
0,24·10 -2
0,12·10 -2
0,00·10 -2
0 1 2 3 4 5
years
Tproof = 1 year
Tproof = 3 years
Tproof = 5 years
1)
PFDavg this value correlates almost linearly to the operating time. It is only valid for the corresponding
selection circuit.
2)
TProof is the interval after which a periodically recurring complete function test (to check the safety function)
must be carried out.
3) PFH is valid for the stated Failure reaction time TReaction of the measuring system. This means that the failure
tolerance time of the complete system must be higher than T .
Reaction
VEGAPULS 54K enamel 51
Min