Harness Groups

Real projects rarely ship as one harness — an engine harness, a dash harness, and a battery harness might all live in the same document. Harness groups give each physically separate bundle its own identity: an automatic label you can rename, section headers in the cut list, and its own sheet in the drawing export.

How detection works

You never assign nodes to a harness. The tool detects harnesses for you: a harness is a connected component of the bundle graph — every connector, splice, and terminal you can reach by following trunk bundles and mated connector pairs is built as one physical assembly, so it counts as one harness.

Relationship	Joins two nodes into the same harness?
Trunk bundle (drawn in the Layout view)	Yes
Mate (two connectors plugged together)	Yes
Schematic wire alone, with no bundle route	No
Nothing (a connector still floating in the schematic)	Not in any harness

Detection is recomputed live on every edit — there is nothing to refresh. Each detected harness gets an automatic name in discovery order: Harness A, Harness B, and so on (continuing AA, AB, … if you somehow need more than 26).

Note

Membership follows the physical routing, not the schematic. Two connectors joined only by a schematic wire — with no trunk bundle between them — stay in separate harnesses, and their wires show up under No harness yet in the cut list until you route them. See Layout for drawing trunks.

Name a harness

In the Layout view, each detected harness shows a small label chip above its top-left-most node, e.g. ⌁ Harness A · 6 (the number is the node count).

1. Click the chip. It turns into an inline text field.
2. Type a name — Engine harness, Dash, whatever matches your build docs.
3. Press Enter (or click away) to save the name. Press Escape to cancel.

To go back to the automatic letter, rename the harness to an empty string — the stored name is deleted and the chip reverts to Harness A-style labels.

Names survive edits

The name is stored with a snapshot of the harness’s member nodes, and on every detection pass each stored name re-attaches to whichever live component overlaps that snapshot the most. In practice this means:

• Growing a harness (adding a branch, inserting a junction) keeps its name.
• Splitting a harness in two gives the name to the half with the bigger overlap; the other half gets a fresh automatic letter you can rename.
• The snapshot only refreshes when you explicitly rename, so normal editing never churns the harness-name entries stored in your project. See File format for where harness names live in the saved document.

Read the cut list by harness

Open a Cut List pane (or export via the ☰ file menu → Export → Wire list / cut list (CSV)). Rows arrive grouped by harness so the table reads as build sections:

• When the document contains more than one harness, a section header row (⌁ Engine harness) precedes each group. With a single harness, no headers appear — nothing to separate.
• Wires whose ends aren’t routed through any bundle yet collect at the bottom under No harness yet.
• The CSV export includes a Harness column as its first field, so a spreadsheet filter or pivot per harness is one click. The in-panel Export CSV button produces the same file.

See Exporting for the full run-down of CSV outputs.

Export one drawing per harness

The technical drawing export is harness-aware. Open the ☰ file menu → Export → Technical drawing (SVG)…:

• Whole layout renders everything on one sheet.
• Below it, one button per detected harness (⌁ Engine harness · 6 nodes) renders a sheet containing only that harness — handy for handing a single assembly to the person building it. The saved file name combines the document and harness names.
• With the PDF format selected and more than one harness in the document, an extra All sheets button produces a single PDF: the whole layout first, then one page per harness, with sheet numbers in each title block.

If the dialog reports No bundles yet, no harnesses have been detected — draw trunks in the Layout view first, and each isolated harness then gets its own sheet.

Tip

Name your harnesses before exporting drawings or CSVs. The names flow straight into sheet titles, filenames, section headers, and the CSV Harness column, so downstream documents stay consistent.

Related pages

• Layout — drawing the trunk bundles that define harness membership
• Exporting — drawings, cut list CSV, BOM CSV
• File format — where harness names live in the saved document