Beckhoff EL2911, Руководство по эксплуатации

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Product description
EL2911 20 Version: 1.0.0
3.5 Safety parameters
Characteristic numbers EL2911-0000
Lifetime [a] 20
Prooftest Interval [a] not required
1
PFH
D
4.50 E-09
PFD 5.00 E-05
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 EL2911 EtherCAT Terminal.
2. Classification according to IEC 61508-2:2010 (chapter 7.4.4.1.2 and 7.4.4.1.3)
The EL2911 EtherCAT Terminal can be used for safety-related applications within the meaning of
IEC 61508:2010 up to SIL3 and EN ISO 13849-1:2015 up to PL e (Cat 4).
Further information on calculating or estimating the MTTF
D
value from the PFH
D
value can be found in the
TwinSAFE application manual or in EN ISO 13849-1:2015, Table K.1.
In terms of safety-related parameters, the Safety-over-EtherCAT communication is already considered with
1% of SIL3 according to the protocol specification.
3.6 Safe inputs and outputs
The safe inputs and corresponding clock outputs are consolidated in a module. This has the advantage that
a two-channel safe sensor can be used on any of the EL2911 channels, and a fault such as cross-circuit or
external feed results in shutdown of the whole module.
The safe output module has a single-channel design.
NOTE
Clocked signals inside a sheathed cable
The clocked signals (clock outputs for the safe inputs) can be used in any way that may be required within
a sheathed cable, since faults such as cross-circuit or external feed result in shutdown of the whole input
module.
NOTE
Safe inputs in Cat.4 / PL e
If two safe input channels in category 4 structure are to be used, any of the EL2911 channels can be used.
3.7 Characteristic curve of the inputs
The characteristic curve of the inputs is similar to type 3 according to EN 61131-2.