Abstract Bypass

Wiring in Modular Wiring Synthesis

When running Modular Wiring Synthesis (MWS), you can generate abstract bypass wiring without physical harness levels. This enables you to evaluate full wiring earlier in the design flow and to generate wiring diagrams (using Capital Schematic Generator for Systems Integrator) before you have any physical harness levels defined. Bypass wires are sometimes required in modular harnesses (for example, for networks).

The system generates wires based on valid combinations of options. It looks for all valid combinations of the options that effect a signal when deciding whether it needs to bypass a splice.

As for Composite Wiring Synthesis, you can use a “Create Bypass Wiring” constraint to control whether the generation of a bypass wire is allowed for a splice or a signal with a particular property or attribute.

Specific Abstract Bypass Wiring Flows

The ability to generate bypass wires in MWS, enables some specific flows.

Figure 186: Abstract Bypass Wiring Flows

Simple

Usage Example of Abstract Bypass Wiring

This video shows the simple example that follows.

This simple Capital Logic Designer design has some devices that are permanently in the vehicle. DEV1 and DEV4.

Figure 187: Simple Capital Logic Designer Design

Two devices are optional (DEV2, DEV3) and they connect to a single signal COND1.

This simple Capital Systems Integrator design has those four devices placed in slots.

Figure 188: Simple Capital Systems Integrator Design

You run MWS without selecting Generate Bypass Wiring.

Figure 189: Generate Bypass Wiring Not Selected

You then visualize the wiring for signal COND1.

Figure 190: Simple Example - Visualized Wiring with No Bypass Wires

Note

The Capital Systems Integrator design has a “Cost of splice” constraint: Cost of Splice = 100.0 where Signal matches Name=.* to minimize how many splices the system creates.

In harness H14, wires are joined to the splice SP103. An inline joins harness H14 with harness H5 where wires go to device DEV3.

Option expressions are visible on the wires (ESC or ABS) to help with visualization.

ABS and ESC are both optional so you expect that the system will bypass the splice in some cases.

You re-run MWS but with Generate Bypass Wiring selected.

Figure 191: Generate Bypass Wiring Selected

You refresh the visualized wiring for COND1.

Figure 192: Simple Example - Visualized Wiring with Bypass Wire

You now get a single bypass wire that goes between DEV1 and DEV4 (the permanent devices).

If the vehicle does not have ABS and does not have ESC, it needs this bypass wire.

If the vehicle has ABS or ESC, the splice has three wires and is required.

Complex

Usage Example of Abstract Bypass Wiring

This video shows the complex example that follows.

This follows on from the simple example.

You remove the Cost of Splice constraint from the Capital Systems Integrator design and re-run MWS with “Delete All Wiring” but not “Generate Bypass Wiring”.

The refreshed visualized wiring for COND1 now has two splices.

Figure 193: Complex Example - Visualized Wiring with No Bypass Wires

This is important because if the vehicle does not have ESC, for example, the top splice SP105 will be a two wire splice.

If ABS is not in the vehicle, the bottom splice SP104 will be a two wire splice.

This means, you expect more bypass wires to be required.

You run MWS with “Generate Bypass Wiring” and refresh the visualized wiring for COND1. There are now three bypass wires.

Figure 194: Complex Example - Visualized Wiring with Bypass Wires

One that goes from DEV1 to DEV4 on the right that is required if the vehicle has neither ABS or ESC.

One from SP104 to DEV4 (required if ESC not in vehicle).

One from SP105 to DEV1 (required if ABS not in vehicle).

Caution

The system has looked at the options on the generated wires and determined under which circumstances it requires bypass wires. If your design is very complex, MWS may generate many bypass wires.

Parent Topic:

Wiring

Capital Systems Integrator User Guide, 2512.2606

Unpublished work. © 2026 Siemens