Combined

Signals and Combined Wires

Normally, each wire in a vehicle is used to implement a single signal. However, in some cases, it is desirable to re-use a wire to implement more than one, mutually exclusive signal. You can achieve this by creating a combined signal and combined wire. Wires in a combined signal can either belong to just one child signal or be shared between all the signals.

Note

It is best practice to use different names for combined (parent) signals and child signals to avoid ambiguity during signal mapping, routing, and wiring synthesis.

Combined signals can contain only child signals of the same type. For example, if a shielded signal is added as a child signal to a combined signal, all child signals for that combined signal become shield signals.

When wires are combined:

• The individual wires are removed from the child signals of the combined signal and the combined wire is added to that combined signal. The reverse action splits a combined wire and adds regular wires into the child signals.

• The attributes and properties are not copied from the wires and splices being combined. Instead, the combined wires and splices use the “Wire Specification” or “Splice Specification” constraints to identify which attributes and properties should be set for them.

• If the wires are attached to a connector on a junction box slot, the cavities or backshell terminations to which the wires are connected lose their signal mappings unless they are connected to other connectors that are not being combined. Figure 279: Before and After Example A for Combining Wires Connected to Slot Connectors

In the above example, two wires going through the slot connector on the right of the slot are combined. Note that the mapping from the splice onto the right bottom cavity is removed because it has no connections after the combination.

Figure 280: Before and After Example B for Combining Wires Connected to Slot Connectors

In the above example, two dashed wires going through the slot connector on the right are combined. Note that the mapping from the splice onto the right bottom cavity is kept because it has a connection to a wire that is not combined.

You can combine wires if the following is true:

• The wires belong to the same harness.

• The wires belong to a combined signal or its child signals.

• The wires are not center-stripped.

• The wires do not belong to a multicore.

• The wires connect to the same two combinable ends and to nothing else.

A combinable end can be one of the following:

• Set of splices The splices must belong to the same harness and carry the combined signal or its children. When the wires between the splices are combined, the splices are combined into a single splice. For example: Figure 281: Before and After Example of Combined Splice

• Set of slot-internal splices The splices must belong to the same slot and carry the combined signal or its children. The splices must connect to the wires through the same slot connector or hole. In the case of a connector, the splices connect to the wires either only through cavities or only through backshell terminations. When the wires between the slot-internal splices are combined, the splices are combined into a single slot-internal splice. For example: Figure 282: Before and After Example of Combined Slot-Internal Splice

• Set of slot device pins through a slot connector The devices must belong to the same slot and carry the combined signal or its children. The slot device pins can belong to slot-internal splices, regular slot-internal devices or a mix of them. The pins must connect to the wires through a single backshell termination or cavity. When the wires between the slot device pins are combined, the slot internal connectivity does not change. Figure 283: Before and After Example of Combined Wire Connected to Slot Device Pins Through Slot Connector

• Single slot device pin through a hole The slot device pin must carry children of the combined signal and belong to a regular slot internal device. The slot device pin must connect to the wires through a single hole. When the wires are combined, the slot device pin loses mappings onto wires that the system combines and gains a mapping to the combined wire. For example: Figure 284: Before and After Example of Combined Wire Connected to Slot Device Pin Through Hole

• Set of cavities or backshell terminations The set must belong to the same inline or interface connector. Cavities and backshell terminations cannot be mixed. Each cavity or backshell termination must carry the combined signal or its children. The combined wire connects to the cavity or backshell termination with the lowest name. For example: Figure 285: Before and After Example of Combined Wire Connecting to Cavities or Backshell Terminations This example shows an inline before and after four wires on the right are combined. Note that the system has moved all of the conductors on mated cavities on the left to the cavity mated to the one to which the combined wire connects. This applies to any conductor that carries the same signal as the wires being combined.

• Combining Wires at a Cavity

• Setting a Constraint to Combine Wires at a Cavity

• Automatic Combination of Physical Multicores During Wiring Synthesis

• Creating a New Combined Signal from Selected Signals

• Adding Selected Signals to an Existing Combined Signal

• Combining Selected Signals with a Compatible Signal

• Removing Selected Child Signals from a Combined Signal

• Uncombining All Child Signals from a Combined Signal

• Creating a New Combined Wire from Selected Wires

• Creating a New Combined Wire from a Selected Set of Wires for a Combined Signal

• Adding Selected Wires to an Existing Combined Wire

• Combining Selected Wires with a Compatible Wire

• Uncombining Wires

• Combining Multicores

• Uncombining Multicores

Parent Topic:

Wiring

Capital Systems Integrator User Guide, 2512.2606

Unpublished work. © 2026 Siemens