Project 2
Aim: Route the wiring harness on the Backdoor of the Vehicle and prepare to flatten the view in CATIA. Apply all packaging rules and industry best practices.
Step 1 Context Assembly
Wiring harness routing shall provide ease in manufacturing, accessibility, easy removal and easy maintenance of attached equipment and routing harness. The wiring harness should be routed in such a way that it is easy to assemble on a vehicle.
The wiring harness should be kept away from sharp environments like sheet metal brackets, panel edges, corners etc. Avoid harness routing and clipping in the blind zone of the operator during harness installation. Ensure that routing meets the clearance requirements with the different surrounding parts. Routing shall provide enough slack for each branch to avoid additional stress on wire and terminal crimping joints but ensure that extra slack does not because wiring harness foul with surrounding parts and impact desired clearance requirements.
Enough clamps should be provided to ensure positive clearance with the surroundings and the safety of the wiring harness.
The branch length should be a minimum of 50mm.
The minimum distance between the clip and the nearest branching point should be 25mm.
The minimum distance between two breakouts should be 50mm.
Limit the no. of branches from a single branch point to 4.
The min. bend radius is to be 1.4.
Consider min 5% slack in the wiring harness if needed.
Create context assembly context assembly will contain 3D CAD data for the engine and engine harness geometrical bundle assembly.
Step 2. Define the connectors electrically
Before adding connectors into the geometrical bundle define all the required connectors electrically.
To define any connector electrically,
- Create required geometrical parameters like bundle connection point, connector connection axis and cavity connection axis (if required) to the connector in the part design workbench.
- Now define connector with electrical properties such as connector connection point, bundle connection point and cavity connection point. Go to the electrical part design workbench and select connector command and input the no. of terminals as per the
Available connector.
- Defining connector connection point using connector connection point command and defining the parameters
- Define bundle connection point using bundle connection point command and define the parameters
- Define cavity connection paint using the cavity connection point command and define the parameters. Hence the connector is defined electrically.
Step 3. Inserting connectors into the geometrical bundles and positioning them.
The connectors are inserted into the geometrical bundle and positioned on the Backdoor
Step 4. Defining mounting clip electrically so that the interconnection connector can be mounted on the sheet metal bracket
To define mounting clip electrically
- First, define the geometrical parameters which are the cavity connection axis in the part design workbench
- Defining electrical properties of the mounting clip by going to the electrical part design workbench.
- Define the clip as mounting equipment using the mounting equipment command.
- Select cavity command and define the parameters
Step 5. Mounting the interconnection connector on the sheet metal bracket
- To mount the interconnection connector onto the sheet metal bracket, first, the mounting clip is mounted on the sheet metal bracket.
- Then the interconnection connector is electrically connected with the mounting clip by using connect electrical devices command in the electrical assembly design workbench.
Step 6. Adding Fir Tree Clips to provide positive clamping for the wiring harness.
- Fir Tree Clip should be defined with electrical properties before inserting into the geometrical bundle assembly.
- First define geometrical parameters such as entry point, entry plane, exit point, exit plane and base
- Go to the electrical part design workbench and define the Fir Tree Clip as support using the support command and define the parameters
- Use the support command again and select the first plane definition as an exit point and exit plane, this is done to obtain wiring entry from either side of Fir Tree Clip.
- Fir Tree Clip is mounted on the existing bolts and screws to provide positive clamping and ensure proper clearance management for the wiring harness routing.
Step 7. Routing the wiring harness to the connectors
Go to the electrical harness assembly workbench and select the geometrical bundle command and select the geometrical bundle in the model tree. Then select the multibranchable command to start the bundle routing and go to route definition.
- The bundle routing starts from the interconnection connector and then to the Fir Tree Clip and the guiding channels.
- Adding branching points wherever necessary using add branch point command
- Adding branches wherever necessary to connect the various connectors to the main branch using add branches command and routing definition into it.
- Add branching points to the wiring bundle and add branches to connect the wiring to the connectors
To add protective coverings on the wiring harness, first, create a protective covering by using the define protection part command in the electrical part design workbench. Select any plane, and define the parameters as per the requirement.
- Go to new and select catalogue document, select add family command and define the type as conduit save the file to create a catalogue for protection tube.
- A catalogue file is created
- Save the file to create a catalogue for the protection tube.
- The created corrugated tube can be added to the catalogue by the store device command and by selecting the catalogue file created for the protection tube which can be used to add protection to the harness as and when required.
- To add a protection tube to the wiring harness, select the light protective coverings command and select the required size protection tube from the catalogue
Step 8. Check bundle connectivity
To check bundle connectivity go to edit, select search option, go to the advanced tab and select the workbench as electrical, type as bundle segment and attribute as fully connected and attribute criterion as true if, you want to check all connected bundle segments and false if you want to check all the unconnected bundle segments.
Now as the branches are fully connected we can proceed further with harness flattening.
Step 9. To create a flattened view of the Backdoor harness
- Create a new product file and save it in the same folder where the wiring harness is saved.
- Go to Electrical harness flattening workbench and select harness flattening parameters and define harness flattening parameters into it
- To import the harness file into the harness flatten the file, select the extract command and go to the harness assembly window and click on the geometrical bundle. The harness routing is added into the harness flatten
- Go to flatten command and select the appropriate face and select all the branches of the wiring harness, the harness is flattened
- Use rotate command to rotate the branches and make the wiring harness routing presentable in the drawing sheet. Following this, the connectors and other devices are also to be manipulated in the assembly design workbench to give a proper view while drafting on the drawing sheet.
- The flattening view is ready and can be used for drafting.
Step 10. Create a drawing of the flattened harness
- Go to new and select drawing to create a new drawing file.
- Select the front view command, go to the flattened harness window and select a suitable face to create drafting of the harness. The wiring harness appears as shown below.
- To make the bundle segments visible right-click on the drawing sheet and go to properties, in the view tab, highlight the 3D wireframe which is always visible in the dress-up settings.
