Considering External Data Routing
in Greater Depth

This section explains how information is retrieved from external data to perform wire group, wire or equipotential routing in CATIA. We assume that the placement and/or linkage of the devices is already correctly performed.

In the exchange data model, the wire or equipotential extremities are used as a link between the routable (wire or equipotential) and a device entity (connectors, equipment, pins).
This link relies on the Id attribute, which represents a unique identifier shared between ECAD and MCAD.
Please refer to Electrical Data Exchange Format as well as Electrical Library User's Guide - User Tasks - Reconciling External Systems and Physical Data.

To know if the wire or equipotential is ready to be routed, CATIA queries the object that represents its extremities. Several alternatives exist:

  • The extremity is a pin:
    • Either the Id attribute is found in the 3D session, this pin is considered as an extremity,
    • Or, the Id attribute is not found for the pin in the 3D session, then, thanks to the connectivity information imported with the external data, the system queries for the parent object (a connector) and this connector is considered as the extremity.

    This means that, even if you decide not to create and map the pin on the 3D devices, the system will be smart enough to take these devices as extremities.
    The 3D data may not go down to the pin level but the routing process can be performed.

    • If the Id attribute of the pin and of its parent is not found, then the extremity is considered as missing.
  • The extremity is a device:
    • Either the Id attribute is found in the 3D session, and this device is considered as an extremity,
    • Or, the extremity is missing and the routing cannot be performed.

To conclude, if any of the extremity is missing for a wire or an equipotential, the status for this extremity is Missing in the Wire List and the routing process cannot be done for this wire or equipotential.


Then, once the system knows what the extremities are for a wire or an equipotential, the routing process is run, with the following steps:

  • A network is built based on bundle connectivity
  • Entry points in the network are retrieved based on bundle connection points
  • Checks are performed between electrical and geometrical bundles to know where the wires have to be created
  • The algorithm is launched to find the route for all the wires/equipotentials
  • The wires are created in the correct electrical bundle with the route found.

Wire Group Routing

A wire group is ready for routing if all its constituent wires and wire groups are ready for routing. This means in particular that all extremities of constituent wires are correctly mapped.