Project 2

AIM: Route the wiring harness on given car body hatch and prepare the flatten view drawing in CATIA V5.

Objective: This project involves the objective to route the wiring harness on given car body hatch and prepare the flatten view drawing in CATIA V5 with all the necessary constraints applicable in Routing. All the packaging rules and industry best practices shall be considered with necessary data of clearance, clipping/clamping section, Harness fixing requirements, harness continuity and assumptions of 3D data that is required to route the wiring harness on to a given engine.

                               

TECHNICAL SPECIFICATIONS AND ASSUMPTIONS:

• Wiring harness routing shall be ease in manufacturing, accessibility, maintainance and removal.
• Aviod routing through small structural holes, bolts, bolted joints, screwed joints to avoid harness puncture
• Provide additional slack to the harness according to the surrounding and harness bending requirements.
• Provide additional slack to the harness branch which connects to the loads and covered with enclosures.
• Avoid routing near sharp edges or over the sharp edges, in case of non avoidable situations addtional protection shoud be provided.
• Ensure harness is routed atleast 100mm away from ABC pedals.
• Enough clips and clamps shall be privided to ensure the positive clearence with surroundings and safety of wiring harness.
• Keep the harness away from engine heat generation components, heating lines and EGR components.
• Avoid direct support of harness on fuel lines routed in engine, in that case a seperator clamp to be provided to satisfy clearence requirements.
• Harness branch length should minimum 50mm.
• Minimum distance between clip and nearest branching point should be 25mm.
• Limit the number of branches from single branching point to 4.
• Harness Protection should be provided according to the surrounding temeperature. 
• Clips/Clamps that are used should be selected such that they are easily available in the market.

The given car body hatch focuses on different areas of study under which comprises of routing harness bundles for two taillamps and two number plate lights which connects the car main electrical system.

For all these four lights a Deustch 2 pole connectrors are used (DT06-2s) and a an Interconnection connector which connects from car body hatch to the main car body wiring harness and is used at a preferred location from where the routing for these lights starts. For interconnection 12 pole connector is used.

As for the mounting parts clips/clamps which are used where ever necessary, hellerman mounting clip and fixing clips are used.

This car BIW body requires a lot of mounting hole provision for he clips, it should be discussed with BIW design team and should be asked for these extra features and it will be finalised by the BIW design team.

CONTENTS: 

Step1: Creating Car body context assembly and Geometrical assembly

Car body hatch context assembly contains 3D data of car body hatch and all the non electrical data are stored in it and also the geometrical bundle assembly which consists of the electrical data needed for the project.

Step2: Defining 2 pole connector electrically.

The 2 pole connector DT06-2S is used for 4 lights 2 for taillamps and 2 for number plate are defined electrically with all the bundle connection point and connector connection points, as shown in the fig below.

                                      

                                     

Placing or mounting clips in the preferred locations of tail gate:

                       

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Step 7: Bundle routing from interconnection connector to all the connectors arranged and all the mounting clips

The  dimensions assigned for bundles, like diameter and bend radius are assumed and actual values are provided at a later stage. From the below figure it is seen that the routing starts from the interconnection connector and goes throung all the clips and then to the all the connectors.

The bend radius for all the bundles is assumed to be 1.4mm

                           

                                   

Adding protective coverings to the bundles

Protective coverings are added to the bundles to avoid any damage, wear and tear to the bundles which might happen during opening and closing of door. In this case blue color PVC tapes are used with start and extremity given wherever necessary through out the bundles as shown in the fig below.

                               

Creating flatten product and Flatten drawing view of harness assembly

Flattened product is 2D representation of harness bundles along with all the electrically defined equipments to present it on piece of drawing paper.

To create flattening product of the assembly working bench should be Electrical harness flattening, name the new product as car body hatch flattening assy and define flattening parameters as shown in the figure, and make sure to use single line foe bundle and double line for PVC tapes for better differentiation.

Once the parametrs are defined , the geometrical bundle assembly should be extarcted in to the flattening product by using the extract option in the work bench. Once the assembly is extracted use the flatten option to flatten the entire assembly.

Now select the front view option and select the plane of the flattened which was selected earlier in the flattening properties.

Now the 2D diagram of flattened model is displayed on the drawing sheet, now to go the that drawing properties and in the view section make sure 3D wire frame is always ON which represents the bundles and make sure the graphic for device is 3D projection for better identification and understanding and single line for bundle and double line for protective coverings, and 3D colors can be added for better look as per the image shown below. 

The connectors namings can also be given by selecting the text option, and drawing frame and title block, BOM table can also be added for better understanding.