Beckhoff EL1904, Operating Instructions Manual

Page: 17 / 46

Product description
EL1904 17 Version: 2.1.1
3.4 Safety parameters
Key figures EL1904
Lifetime [a] 20
Prooftest Interval [a] not required
1
PFH
D
1.11E-09
%SIL3 1.11%
PFD 8.29E-05
%SIL3 8.29 %
MTTF
d
high
DC high
Performance level PL e
Category 4
HFT 1
Element classification
2
Type B
1. Special proof tests are not required during the entire service life of the EL1904 EtherCAT terminal.
2. Classification according to IEC 61508-2:2010 (chapter 7.4.4.1.2 and 7.4.4.1.3)
The EL1904 EtherCAT Terminal can be used for safety-related applications within the meaning of
IEC 61508:2010 up to SIL3 and EN ISO 13849-1 up to PL e (Cat4).
For the calculation or estimation of the MTTF
d
value from the PFH
D
value, further information can be found in
the TwinSAFE application guide or in ISO 13849-1:2015 Table K.1.
3.5 Characteristic curve of the inputs
The characteristic curve of the inputs is similar to type 3 according to EN 61131-2.
Fig. 5: Characteristic curve of the inputs