Project 2

AIM - Route the wiring harness on given car's BACKDOOR 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 given car back door.All types of packaging rules and constraints have to be considered while routing the harness.All the necessary details like clearance/clamping section,harness fixing requirements,harness continuity should be provided in order to design the wiring harness.

Above figure shows the given car back door for which wiring harness has to be designed.

The wiring harness packaging rules and the industry best parctices that have to be followed to complete this project are as follows:-

1.Easy manufacturing,installation,removal,and maintainence have to be considered while designing the wiring harness.

2.Routing through small structural holes shall be avoided to minimize chaffing and handling during installation.

3.Avoid harness routing and clipping in the blind zones.

4.Provide additional slack if needed according to the surrounding and harness bending requirement.In this project we choose slack value as 1-5%.

5.It should be made sure that there is no case of fouling while designing the wiring harness in the CAD environment.Additional clips/clamps may be used to avoid fouling.

6.Avoid harness routing near sharp edges or else provide protection over the harness.

7.Enough mounting equipment such as clips and clamps should be provided.

8.The branch length should be greater than 50 mm.

9.The minimum distance between the clip to thge branch point should be minimum 25mm.

10.The wiring harness should be easy to assemble and easy to excess.

The given car back door has multiple area of interest,the two taillights and the two license plate lights have to be wired and connected to the car electrical main system.

In this project we used 4 Deutsch 2-pole connector two for the tail lights and the remaining two is for license plate light.

The car body will also have an interconnection connector which will connect the car backdoor wiring harness to the main body harness of the vehicle.We used 12-pole electrical connector as an interconnection connector.

For the mounting solution,we choosed 2 HellemannTyton 151-01844 and 13 C-0626897-03 FIRR TREE clips .

CONTENT:-

STEP 1- Creating assembly BACKDOOR harness context.

STEP 2- Defining 2 pole connector electrically.

STEP 3-Adding 2-pole connectors to the two tail lights and the two licence plate lights.

STEP 4-Defining and locating interconnection connector.

A 12pole "C-776438-4" connector is used as an interconnection connector.The 3-D CAD data file for the required connector is downloaded from TE.com.Connector is electrically defined and mounted near the already present slot on the car back door body as shown below-

STEP 5- Defining clip mounts as supports.

STEP 6-Locating and placing clips in the desired locations.

STEP 7-BUNDLE ROUTING

We start the bundle routing from the interconnection connector.The bundle diameter of the main trunk is assumed to be 15mm.The bundle diameter lerading to the 2 pole connectors is assumed to be 6mm.Bend ratio is assumed to be 1.4 and slack value is between 1-5% is used whenever needed.

STEP 8-Protection Covering.

Protective covering is used to keep the bundle together and protect the wiring harness from wear and tear.For the current harness assembly we used a blue colour corrogated tube.

STEP 9-Checking Bundle Continuity.

First,we have to make sure that the multi-branch able is selected and then we have to go in "EDIT>SEARCH>ADVANCED>ELECTRICAL WORKBENCH>TYPE-BUNDLE SEGMENT>ATTRIBUTE-FULLY CONNECTED."

Selecting the "TRUE" option will ahow all the connected bundle segments while selecting "FALSE" will show all the non-connected bundle segements.

In our case we select TRUE and search for results.All the bundle segments are highlighted and found showing that all the bundle segments are electrically connected.

STEP 10-Create flat-pattern of wiring harness bundle.

To make a flattened view of any wiring harness we should be working in the Electrical Harness Flattening workbench of CATIA V5.We should also make sure that the flattening file is saved in the same folder where we have all the parts of the harness assembly.

While defining the Harness Flattening parameters make sure to use the "single Line" for the bundle segment and "Double Line" for the Protective covering.

Extract and bring the bundle assembly into the car body flattening product file and then flatten the harness along YZ Plane.

Now we used Roll command for better representation of the wiring harness.It should be noted that we have YZ-Plane as the flattening plane so we should make sure that we roll the bundle segment only along YZ-Plane.

STEP 10-Creating a flatten-drawing view for the wiring harness assembly.

Above figure shows the flatten drawing view for the wiring harness assembly.