NX Electrical Routing: Wire Harness and Formboard Practitioner Tips

Combined notes from two Siemens reseller/training-partner articles (Saratech and PLM Tech Talk / i GET IT Learning) on the practical mechanics of building and documenting wire harnesses in NX Routing Electrical — the kind of "gotcha" detail that's easy to miss in official help.

The #1 beginner mistake: forgetting to enable Wire Harness mode

Both sources independently call out the same pitfall as the most common mistake new users make: launching the Routing application without explicitly enabling Wire Harness functionality. If you don't do this, key harness features are simply unavailable and nothing obviously tells you why.

Fix: On the Application tab under Routing, choose More, and confirm "Harness" is highlighted in the Electrical group before starting work. (Source: How to Create and Flatten a Wire Harness in NX, Saratech; corroborated in NX Electrical Routing – Formboards, PLM Tech Talk)

Prerequisites before you start a harness

• Have the appropriate licensing for wire harness functionality confirmed — this is a separately licensed capability, not automatically included.
• Have qualified parts (connectors and other harness hardware) already defined by your CAD administrator. Harness design assumes a populated, qualified parts library exists — it is not a "start from a blank part" workflow.
• Customize part attributes in Customer Defaults under Routing > Formboard ahead of time so formboard output matches your documentation standards.

Always model harnesses inside an assembly context

Create wire harnesses within the full product assembly, not a standalone part file, so you can verify stock lengths against the real installation envelope and confirm there are no collisions with adjacent components as you route. Designing in isolation defers collision discovery to a much more expensive point in the process.

Formboards: what they are and why they matter

A formboard is a flat, full-scale representation of the 3D wire harness, used because wiring harnesses are typically manufactured by hand on a flat pegboard/table using the formboard drawing as the physical layout guide. The critical requirement is that the manufactured (flat-built) harness must physically fit the as-designed 3D product — a formboard that doesn't correspond correctly to the 3D geometry can produce a harness that requires forcing into place during installation, straining wires and connectors. (Source: NX Electrical Routing – Formboards, PLM Tech Talk)

NX's flatten operation preserves electrical connectivity and relative connector positions while laying the bundle onto a single plane, and automatically:

• Identifies minimum bend radius violations
• Calculates wire lengths and bundle diameters
• Produces the formboard drawing itself as manufacturing documentation

Multi-harness flattening rule: you can select and flatten more than one harness at once, but all selected harnesses must be "fully connected" — meaning they share at least one segment, reference connectors joined by a port-to-port connection, or have a bond constraint between them. Unconnected harnesses cannot be flattened together in a single operation.

Practical formboard production tips

• Determine your available print sheet sizes before creating the formboard, not after. Discovering a sheet-size mismatch after layout means time-consuming manual repositioning of the whole flattened harness.
• Use View Orient when inserting new formboard views to get connector faces properly aligned in the drawing.
• For cleaner formboard visuals, double-click into views and enable Front/Back Clipping under Perspective settings.
• Use View Dependent Edit (right-click a view) to selectively hide components that clutter a specific formboard view without affecting the underlying model.

Business case cited by resellers

Both articles frame formboard automation primarily as a cost/cycle-time argument to management: manual formboard creation is described as something that "typically consumes hours or days when done manually," whereas generating it from the already-connected 3D/electrical design is comparatively fast and, because the harness is validated against the real 3D envelope before it's ever built, reduces physical prototype iterations and post-manufacture rework.