Project 2

Aim: Route the Wiring Harness on given Car body and prepare flatten view drawing in Catia V5

Objective: The objective of this project is to route the wiring harness and prepare flatten view drawing for the tailgate of the car. All types of packaging rules have to be considered while routing the harness and industry based practices shall be demonstrated in harness design. All necessary details like clearance, clipping/clamping selection, harness fixing requirements, harness continuity should be provided in order to design the wiring harness.

Assumptions:

1. Wiring harness should be routed in such way that it is easy to assemble and access.
2. Easy manufacturing, installation, removal and maintenance have to be considered while designing the wire harness.
3. Wiring Harness should be kept away from sharp environment like edges, corners etc.
4. Avoid harness routing and clipping in the blind zones or hard to reach areas during harness assembly or service.
5. Provide additional slack if needed according to the surrounding and harness bending requirement. If harness is passing through the closures/doors or tail gates then envelope dimensions during opening and closing of doors shall be considered to provide the slack. Check the harness slack requirements with open and close conditions to avoid excess slack.
6. Routing through small structural holes and openings shall be avoided. To minimize chaffing and handling of the wiring harness during installation.
7. It should be make sure that there is no case of fouling while designing the wiring harness in the CAD environment. Additional mounting equipments like clips/clamps may be used to avoid fouling.
8. Use of rubber grommet is recommanded if harness is passing through sheet metal panels. Example- firewall, passing to door, tail gate etc.
9. The branch length should be greater than 50mm.
10. The minimum distance between the clip and branch point should be at least 25mm.
11. The minimum distance between the two branch points should be at least 50mm.
12. Clips/clamps used for the wiring harness should be easily available in the market to avoid extra cost for custom mounting solutions.

• Now, we have to route wiring harness for two tail lights and two number plate lights, and connect them to main electrical system of car.
• For two tail lights and two number plate lights, we are using 8-pole connector and 2-pole connector respectively.
• A car body also have an interconnection connector which will connect the wiring harness of tail gate of the car body to the main harness of the vehicle.
• We will use 12-pole electrical connector with a mounting clip as an interconnection connector.
• The bend ratio for all the bundle segment is considered to be 1.4 

• We have created context assembly for the tail gate of the car as main assembly as shown in above figure.
• This context assembly contains the 3D cad data for the tail gate of the car and car tail gate harness geometrical bundle.

 Defining connectors electrically

• Here, we will use 2-Pole and 8-Pole and C-1563689-1 connectors for this assembly and for that we have downloaded these connectors from TE.Com
• We should have to define it electrically that is to define geometrical parameters, bundle connection point and connector connection point.

connector 1

connector 2

connector 3

clamp

firr-tree

Fir Tree Wiring Harness Supports are fixed into a pre-drilled hole in a panel, and support the cable loom running within a vehicle, domestic appliance or other electrical equipment. Cables can be fixed to the Harness Support by tape or by using Cable Ties.

Checking bundle continuity

• First, we have to select multi-branchable and go through the sequence as Edit>Search>Advanced>Workbench-Electrical>Type-Bundle Segment>Attribute-Fully Connected.
• After selecting 'True' condition will show all the connected bundle segments while selecting 'False' condition will show all the non-connected bundle segments.
• Here, we have selected 'True' condition and search for the results. All the bundle segments are highlighted and showing that all the bundle segments are connected electrically as shown in below image.

 Adding protective covering to the harness bundle

• After bundle routing, we have to add protective covering to the harness bundle so that it will get protected from the damage. 
• Here, we have used PVC tape for the current harness assembly.
• We have given start and end extremity wherever needed for the PVC tape as shown in below image.

 Create flatten view of the wiring harness bundle

• To create a flatten view of the harness assembly, we have to work in Electrical Harness Flattening workbench in Catia V5.
• Also, we have to make sure that the flattening file is saved into the same folder where we have all the parts of the harness assembly. 
• As shown in below image, while defining the wiring harness flattening parameters make sure to select Single line for bundle segment and Double line for protective covering.

 Flatten Drawing 

multiple view

Conclusion

Routing of the wiring harness for the car Backdoor assembly has been succesfully done and prepared flatten-view drawing in Catia V5 as per the design requirements.