
6
Errors (cross circuits, short circuits), which can be prevented by correct installation (e.g.,
protected cable installation, isolated cable installation, double insulation, use of ferrules)
are not described in the following tables.
Therefore, for example, only errors between relay outputs, which are on the same
connector, are described. For example, in the event of correct installation, cross circuits
with relay outputs of other connectors cannot occur.
When assigning the contacts, observe the potential areas according to Section "Safe
digital relay outputs (floating contacts)" on page 2-4.
Please observe the load capacity of the relay outputs according to the technical data in
"Safe digital relay outputs (floating contacts)" on page 2-4 and protect the contacts against
overload using an appropriate fuse.
6.2
Notes on the protective circuit for external
relays/contactors (free running circuit)
Figure 6-1
Example of the free running circuit for an external relay
A protective circuit via the relay contacts is not permitted.
For all examples, please also observe the measures specified in the individual tables,
which must be taken to achieve the specified SIL/SIL CL/Cat./PL and all measures
according to standards EN 61508, EN 62061, and EN ISO 13849-1 to achieve the
specified SIL/SIL CL/Cat./PL.
WARNING: Disregarding this warning may lead to the loss of the safety function
–
When operating the safety-related segment circuit, observe the information in the
application note for the safety-related segment circuit. Ensure that an external
supply cannot be connected in the safety-related segment circuit.
–
An interrupt of the output signals must not result in a hazardous system state.
–
Ensure that cross circuits with external signals cannot be created.
–
Ensure safe isolation to the PELV signals.
K 1
6 9 4 0 0 0 2 1
6-2
User manual IC220SDL840 -
May 2018
GFK-2734