Project 2

AIM

To route the wiring harness on given car body back door and prepare flatten view drawing in CATIA v5.

OBJECTIVE

• Define all mechanical connectors electrically and save it in catalogue.
• Place required connectors on the back door CAD data.
• Place the fir tree clips at the required positions by following packaging rules.
• Create the wiring harness routing with the all electrically defined connectors and mounting equipment.
• Create the branching point at the required locations to create sub branches and connected to various connectors in the geometrical bundle.
• Apply protection covering as required.
• Create wiring harness flattening for the final geometrical bundle.
• Using the drafting workbench, create a drawing sheet with the flattened wiring harness.

PACKAGING RULES

• Distance between two clamps on a straight branch should be maximum of 200 mm.
• The minimum branch length should be 50 mm.
• The minimum distance between clips and nearest branching points should be 25 mm.
• The minimum distance between two straight connection points should be 200 mm.
• The minimum distance between two breakout points should be 50 mm.
• To limits the number of branches from a single branch point to 4.
• Enough clips clamps shall be provided to ensure positive clearance with surrounding and safety of wiring harness.
• Fir tree clip and other clips can be added to the geometric bundle as they are electrically defined and are part of wire harness routing and should be provided with thw wire bundle package.
• Enough slack should be provided to the to the wiring harness which helps not to get damaged during opening and closing of back door.
• Easy manufacturing, installation, removal and maintenance have to be considered while designing the wiring harness.
• The wire routing should be done keeping in the mind the cost effective of bundle package.
• To avoid the harness routing and clipping in blind zone of the operator during the assembly and the service.
• To provide the proper slack at the end of the connector so that there will be no tension on the wire bundle.
• To avoid the sharp edges on the sheet metal parts and if it is not possible then provide the protection parts to prevent the damages of the wire bundle.
• Routing through small structural holes and opening shall be avoided. To minimize chaffing and handling of wiring harness during installation.
• To provide the separate branch points for seperate the connectors to ensure poka-yoke.
• The bend ratio for all wire bundle segment is considered to be 1.4

Step 1- Download back door CAD data from the given source

Step 2- Creating the context assembly

Context assembly is nothing but the product file which contains the back door 3D cad data and back door geometrical bundle. Here the geometrical bundle product contains all the connectors and clips which are electrically defined for the assembly

• Create new product file and rename it as back door harness assembly context.
• Add back door CAD data into the context assembly and also creating the geometrical bundle product file inside the context assembly.
• Define the geometrical bundle product file electrically using the geometrical bundle command.

Step 3- Add required suitable connectors from the connectors catalogue.

Back door harness required the following connection connector.

• Inter connection connector - 1
• Top mounted stop light connector - 1
• defogger connector - 2
• brake line assembly connection - 2
• Number plate light connection
• Wiper motor connection

Inter connection connector 1-174357-2

• DT06-4S Used for brake light assy.

• 174359-2 Used for wiper motor

DT06-3S-PP01 Used for number plate and defogger connection

DT06-4S Used for high mount stop light

Step 4 - Placing fir tree clips to required positions to ensure proper harness routing throughout the assembly.

• Ensure no fouling of harness to the back door Sheet Metal components.
• Enough clamps should be provided to ensure the positive clearance with surrounding and safety of wiring harness. Distance between two clips/clamps on a straight branch should be maximum of 200 mm. However the clamping requirement should be decided based on the harness bending and mounting arrangements.

Step 5 - wiring harness routing

• Add branch point at the minimum of 25 mm distance from clips and clamps to create new sub branches connecting various connectors.
• Minimum length of bundle should be 50 mm.

Final geometrical bundle

Applying protective covering

Step 6 - Electrical continuity check

We need to ensure that the entire bundle is fully connected.

• Go to edit and then click on search command
• Go to advanced
• Select the workbench as electrical, type as bundle segment and attribute as fully connected
• The select should be as TRUE or FALSE and click search to see the connectivity analysis result.

Step 7 - wiring harness flattening

We need to convert the geometrical bundle into a flattened wiring harness in the Electrical Harness Flattening Workbench.

Step - 8 Flattened harness view in the drawing sheet

Create a drawing file for the flattened harness product.

First, we need to make sure that in the flattened parameter setting bundle and protective covering having different graphical representation which are

Bundle segment - Single line representation.

Protective covering -Double line representation

• Create a new drawing file in the draft work bench.
• Insert the flattened harness product into the drawing sheet using view option and selecting front view command
• Modify the drawing sheet view with different parameters

Final back door harness drawing

Conclusion

Car back door wiring harness assembly has been successfully completed considering all packaging rules and industrial standards, wiring harness flattening and flattened view drawing preparation are also done by using CATIA.