Typically, in real world applications a connector of one device is not plugged directly into the connector of another device. You will find a piece of cable in between.
As cables are often a delicate part of a system and could be worn down if connected to a moving machine part, it can be helpful to get information what kind of cable is used and where it is connected directly from the system. Be aware that a cable can have more than two ends (Y-Cable, Bus Cable, Cable Tree).
Part2 allows you to include information in the model as needed, from basic items to in depth detail.
In the example above we saw a Controls reference between the lighting controller and Lamp1.
Now we will add a cable to the model that provides this control connection.
As in the last example we now have two paths from Controller to lamp that stand for the same relation. We again may use a reference refinement to give the information that the Controls reference is provided by that cable connection.
Figure 63 – Reference Refinement of the Controls Reference
ReferenceDescription Value of ControlPath1
SourceNode:LightingController1
ReferenceType:Controls
IsForward: TRUE
TargetNode:Lamp1
ReferenceRefinement of ControlPath1
{
ReferenceListEntry
ReferenceType:HasContianedComponent
IsForward: TRUE
TargetNode:PhysicalInterface_ LC_LampPowerA
ReferenceListEntry
ReferenceType:IsPhysicallyConnectedTo
IsForward: TRUE
TargetNode:Cable_LC_LU1;
ReferenceListEntry
ReferenceType:IsPhysicallyConnectedTo
IsForward: TRUE
TargetNode:PhysicalInterface_Lamp1_Power;
ReferenceListEntry
ReferenceType:HasContianedComponent
IsForward: FALSE
TargetNode:Lamp1;
};
Such control flows often include multiple devices which are part of the communication. If the IPC sends a software trigger to the lighting controller via an Ethernet connection, the signal may have to pass an Ethernet switch. Modeling such details gives you the possibility to do sophisticated error analysis later.
Figure 64 – Reference Refinement of the Controls Reference
ReferenceDescription Value of ControlPath5
SourceNode:ComputingDevice1
ReferenceType:Controls
IsForward: TRUE
TargetNode:LightingController1
ReferenceRefinement of ControlPath5
{
ReferenceListEntry
ReferenceType:HasContianedComponent
IsForward: TRUE
TargetNode:PhysicalInterface_CD_Eth;
ReferenceListEntry
ReferenceType:IsPhysicallyConnectedTo
IsForward: TRUE
TargetNode:Cable_CD_Switch;
ReferenceListEntry
ReferenceType:IsPhysicallyConnectedTo
IsForward: TRUE
TargetNode:Ethernet Switch;
ReferenceListEntry
ReferenceType:IsPhysicallyConnectedTo
IsForward: TRUE
TargetNode:Cable_LC_Switch;
ReferenceListEntry
ReferenceType:IsPhysicallyConnectedTo
IsForward: TRUE
TargetNode:PhysicalInterface_LC_Eth;
ReferenceListEntry
ReferenceType:HasContianedComponent
IsForward: FALSE
TargetNode:LightingController1;
};
If the IPC is currently unable to control the lighting controller, the reference refinement provides the information that a service technician not only will have to check the IPC and the controller, but that there are two cables and an Ethernet switch involved that could be causing the problem.