Defining the Harness Wiring Diagram in Altium Designer

Parent page: Harness Design

Creating a New Harness Wiring Diagram Document

The individual wired connections within the harness are specified in the Harness Wiring Diagram (.WirDoc). Add this document to the Harness project from the Projects panel by right-clicking on the project entry and then selecting Add New to Project » Harness Wiring Diagram from the context menu (or use the File » New » Harness Wiring Diagram command from the main menus).

Add a harness wiring diagram document to the harness project from the Projects panel's right-click menu.

A new blank document will open. To proceed, save the new harness wiring diagram document using the File » Save As command from the main menus.

Options of a wiring diagram document can be configured in the Properties panel in its Document Options mode, which is accessed when no object is selected in the document's design space. The main settings are:

• In the General region of the panel's General tab – select the measurement units that apply to the wiring diagram document and its graphic elements and set the grids to enable easier placement. Altium Designer offers three grid types: visible grid for navigation, snap grid for placement and snap distance for aiding the creation of connections.
• In the Page Options region of the panel's General tab – configure document sheet size and title block or select from available schematic templates (*.SchDot).

 
The Document Options mode of the Properties panel (the General and Parameters tabs)

Synchronizing Multi-board and Harness Projects

When the harness project is part of a Multi-board design project, the harness wiring diagram can be synchronized from the Multi-board schematic document data. To do so, select the Design » Import Changes From <Multi-board Project> command from the main menus.

If the Multi-board schematic document contains more than one harness connection definition, the Select Harness Definition dialog will open. Specify the definition that relates to the current harness project.

The Select Harness Definition dialog

The Engineering Change Order dialog will then open showing the harness connector parts and harness nets that were defined in the Multi-board schematic, which will form the basis for the harness wiring diagram.

The Engineering Change Order dialog

After executing the changes (Execute Changes), the data from the Multi-board schematic document are imported into the harness wiring diagram. The connectors, each represented on the wiring diagram by its symbol, will appear in the wiring diagram, initially in arbitrary positions.

Initial positions of connectors on the wiring diagram right after import. Change their positions as needed.

Netlines will be shown between the pins to represent the logical connections defined in the Multi-board schematic. Note that at this stage, there are no physical wires in the design.

Working with Components

Drag the components to the desired positions, using the Spacebar to rotate the components by 90 degrees and the X and Y keys to flip them horizontally and vertically, respectively.

The harness wiring diagram after moving the components.

As well as synchronizing harness connectors from the Multi-board schematic document, components can also be placed manually into the wiring diagram. This allows connectors to be placed in a standalone harness project (that’s not part of a Multi-board project), but also allows additional components to be placed in a wiring diagram that is part of a Multi-board project.

Use the Components panel to place the symbols of the required components. The component placement process is similar to that in the schematic editor. Refer to the Components Panel section of the  Searching for & Placing Components page to learn more.

Note that there will be no net lines shown for manually-added components, as there is no higher-level logical design to drive them.

Click a connector in the design space to present its options in the Properties panel.

The Harness Component mode of the Properties panel displaying the General, Pins, Crimps, and Associated Parts tabs

Creating Connectivity in the Wiring Diagram

Physical wires are placed in the wiring diagram document by selecting the Place » Harness Wire command from the main menus or the Harness Wire command in the editor's Active Bar.

After selecting the command, click a pin of a connector symbol (a red cross appears at the cursor when it’s over a pin connection point) to place the start point of the wire, and then click another pin to place the endpoint of the wire. Right-click to exit the command and confirm the placement of the wire, or click the start point of another wire.

Placing a wire representing a physical connection

When placing a harness wire, press Shift+Spacebar to cycle through placement modes. The mode specifies how corners are created when placing wires and the angles at which wires can be placed.  While in the 90 Degree or 45 Degree mode (true orthogonal modes), press Spacebar to cycle between the Start and End sub-modes.

In the example shown above, note that the netline connecting P1[1] and P2[1] disappears, but the netline connecting P2[1] and P3[1] remains, as that connection has not yet been completed with a wire.

When placed and selected, a harness wire’s vertices can be dragged to change the angle between two adjacent sections.

Select a wire in the design space to change it in the Properties panel. From the panel, you can rename the selected wire, change its width and color and add parameters that can be shown or hidden in the design space.

When two wires are connected in a T-type fashion, a splice is placed automatically at the location of the T-junction, as shown in the image below.

The Harness Wire mode of the Properties pa nel

Crimps

Socket crimps can be assigned to a component. To do this, select a harness component in the design space and open the Properties panel. On the Crimps tab, select a pin, then click . In the Select Connector dialog that opens, browse to and select a component from your available libraries. Pins with assigned crimps are denoted by the   symbol in the design space. An example is shown in the image below.

Adding Cables

To define one or more wires as added to a cable, you can place a Cable object on the wiring diagram using the Harness Cable command from the Active Bar or the Place main menu.

Place a Harness Cable to define one or more wires as added to a cable. Note that when a cable object is selected, the wires covered by this cable are highlighted in the design space.

Properties of a placed Cable object (its location, visual representation and parameters) can be configured in the Properties panel when the object is selected in the design space.

The Cable mode of the Properties panel

Unconnected Wires

A wire end should not be unconnected. Unconnected wire ends are indicated with a solid square.

An indicated unconnected wire

Place a No Connect object at the end of a wire that should remain unconnected.

Properties of a placed No Connect directive (its location and visual representation) can be configured in the Properties panel when the object is selected in the design space.

The No Connect mode of the Properties panel

Adding Splices and Taps

In design situations where a new wire should be connected to an already placed wire, a Splice or Tap must be placed first.

• Splice – the original wire is split into two separate wires by the splice.

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  A splice placed on a wire. Note that the splice splits the original wire into two in the splice location.

• Tap – the original wire remains unbroken.

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  A tap placed on a wire. Note that the tap does not split the original wire.

Use the commands from the associated menu of the Active Bar to place a required object.

Properties of a placed splice or tap (its location and visual representation) can be configured in the Properties panel when the object is selected in the design space.

The Harness Splice mode of the Properties panel

The Associated Parts region of the Properties panel allows parts such as heatshrinks to be assigned to the selected entity, which will be reflected in the project's BOM.

Wire Twisting and Shielding

Wires can be denoted as twisted together by placing a Twist symbol. Select the Twist command in the editor's Active Bar to place a Twist symbol.

The Twist symbol can be placed across two or more wires. In the example below, the red and green wires are twisted together, and the yellow and orange wires are twisted together.

Place a Twist symbol to denote two or more wires as twisted. Note that when a Twist is selected, the covered wires are highlighted in the design space.

The properties of a placed twist (its location and visual representation) can be configured in the Properties panel when the object is selected in the design space. The Twist Objects region of the panel lists wires covered by the selected twist.

The Twist mode of the Properties panel

A shield (with or without a drain wire) can be attached to a group of wires by placing either a Shield or Shield with Connection. Use the commands from the associated menu of the Active Bar to place a required object.

In the example below, all four wires are shielded by a shield without and with a drain wire.

Placed Shield. Note that when a Shield is selected, the covered wires are highlighted in the design space.

In the next example, the same four wires are shielded by a shield with a connection. If the shield is not supplied with a drain wire, a wire has to be placed between the shield and the shield’s connection point.

Placed Shield with Connection. Note that when a Shield with Connection is selected, the covered wires are highlighted in the design space.

If the shield is supplied with a drain wire, a line (Place » Drawing Tools » Line) can be used to connect the shield to its connection point.

Properties of a placed Shield or Shield with Connection (location and visual representation) can be configured in the Properties panel when the object is selected in the design space. The Shield Objects region of the panel lists wires covered by the selected object.

The Shield mode of the Properties panel

An example of a complete wiring diagram is shown below.

An example of a completed harness wiring diagram