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Manual – MOVIDRIVE® MDX61B Safety Module Option MOVISAFE® DCS..B
12
Diagnostic values
Appendix
12.5.2 Digital outputs
General assessment of the diagnostics coverage (DC) for digital outputs according to EN ISO 13849-1.
INFORMATION
• Use the manufacturer's specification (MTTF
d
, FIT values, B
10d
value, etc.) for a
safety assessment of the output subsystem when using external elements in the
switch-off circuit, e.g. for switching amplification.
• The DC values listed in the table should be applied conservatively to ensure com-
pliance with the boundary conditions ("Comment" column).
• Fault exclusions are permitted according to the relevant standards. The specified
boundary conditions must be permanently ensured.
• When using elements to amplify signals in safety circuits, the function of these
elements must be monitored using suitable feedback contacts, etc. (see wiring
examples). Suitable feedback contacts are contacts that are connected with the
contacts in the cut-off circuit in a forced-switching manner.
Measure DC
value
Remark Use
Cross comparison of output sig-
nals and intermediate results in
the logic (L) and temporal monitor-
ing of the logical program run as
well as detection of static failures
and short circuits (with multiple
inputs/outputs).
99% When using elements to
amplify switching (exter-
nal relays or contactors),
the measure is only effec-
tive together with the
feedback function of
switch contacts (EMU
function).
Monitoring of outputs with
direct function as safety
circuit, or monitoring of safety
circuits with elements to
amplify switching in conjunc-
tion with feedback function of
their outputs.
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