S-DIAS SAFETY CPU-MODULE
SCP 111-2
08.09.2022
Page 53
Here, (in contrast to the read interface connections, where you have to specify either the
module or the IP address of the source on the read side) neither the host nor the node has
to specify exactly how the connection is established.
On the host side, the number of nodes that can be connected to this host can be set (similar
to the number of frames for the interface connections). The outputs of the host are provided
to the nodes as inputs. The outputs of the nodes are AND-linked in the host to its input signals
(Safe_Input1 at the host corresponds to the AND link of all Safe_Output1 of connected
nodes). Whereby here, what default value a non-existent node should have for this link, as
well as whether an error should be triggered with a connection loss on the individual channels
can be set.
On the node side, a special feature of the I/Os is that the fourth safe output (S_Disconnect)
must be used. When this receives the value Safebool_TRUE, the connection to the host is
terminated. This ensures that during and after separation, the rest of the machine can
continue running unaffected.
The other safe signals can be used as desired, but it must be ensured that for the
interconnected machine parts, the individual signals have the same meaning. If, for example,
Safe_Input1 in the host has the meaning of an emergency stop, all connected nodes must
have an emergency stop connected to their Safe_Output1 accordingly. However, the
