Project 1

In this project, we aim to route the wiring harness on given V-16 Engine Class-A surface, and prepare flatten view and wiring harness drawing in CATIA V5. All types of packaging rules are considered while routing the harness. All necessary details like clearance, clips, clamps, harness channels, harness continuity is considered while designing the wiring harness.

Engine Sensor-connector requirements:

• The Engine is a 64 valve, 16-cylinder Engine. A total of 16 injectors, where 8 injectors are used for 8 cylinders on right side and 8 injectors are used for 8 cylinders on left side. There are 4 cam-shaft sensors. Generally, 4-pole connectors are used for fuel injectors and Cam shaft sensors of the engine.
• The engine will also have an interconnection connector which will connect the engine wiring harness to other parts of the vehicle and also power supply. We will be using a 12-pole electrical connector with a mounting clip feature as an interconnection connector.
• We will be using a 2-pole connector for two oil pressure sensors, a coolant temperature sensor, Speed sensor and a Neutral-transmission sensor.
• A total of 25 Sensors/Connectors are utilised.
• A plastic guiding channel (2 numbers), each is used to provide proper path for wiring harness near the fuel injector connectors.

Assumptions:

• Clips and clamps are provided as per requirement, to mitigate harness fouling while designing the wire harness. And provide enough tension to the harness bundles.
• When required, an additional slack of 5-10% is provided.
• Care is taken to avoid routing on sharp edges and are also provided with protective covering over the harness.
• Clearance distance of at least 200mm is maintained from heat generating components.
• Branch length is greater than 50mm.
• Minimum distance between two branch points is at least 50mm.
• The wiring harness should be easy to assemble and easy to access.
• The bend ratio for all the bundle segments is assumed to be 1.4

Creating Context Assembly

A Context Assembly will contain Engine Surface data, Wiring Harness Geometrical Bundle Assembly, Connector Sockets and supporting clamps.

Defining Harness Components Electrically

Connectors

All connectors, in the electrical part workbench

• Are defined as Connectors, by providing the number of pins available for connection.
• Bundle connection point is defined.
• Connector connection point is defined.
• For Interconnection Connector C-776438, Cavity connection point is also defined since mounting clip must be assembled.
  
  Connector-1563689
  
  
  Connector-282080-1
  
  
  Connector - 173090-2
  
  
  Connector- 776438 and Clip 1924487
  
  
  Clips
  All P-Clamp and Furr-Tree Clips
• Are defined as support equipments and accordingly, bundle entry-exit planes and points are defined along with base plane as reference.
  
  
  
  Guiding-Channel
• Two plastic Channel assembly consisting of Channel-upper and Channel-lower are defined as Mounting Equipment.
• The guiding channel has 8 openings for connector connection, so all 8 openings are defined as bundle connection point and one more bundle connection point at the main entry of the channel.
  
  

Importing Electrical Components to the Geometrical Bundle

• A catalogue is created consisting of all parts required for the harness assembly and are imported to geometrical bundle from there.
• Since Engine is a critical part and this is just a conceptual design, all connectors are placed in its respective position by using manipulation tools along with compass, snap, and smart move features.
  
  
  
  
  

Adding L-Clip

A sheet metal clip is provided to mount the interconnection connector. The clamp should be mounted on the existing bolt as shown below. This clip should have anti-rotational features. All the design ideas must be approved by the engine design team so that there will not be any disturbance for the smooth working of engine in real time.

Electrical Harness Wiring

P-Clamp:

• The main electrical branch starts from Interconnection Connector. And is routed along the periphery of the engine using P-Clamps which are bolted to the engine with existing engine bolts.
  

Furr Tree Clip:

• To route harness to the pressure sensor, which must pass over a sharp edge, Furr tree clips are utilised to avoid fouling and to maintain proper tension in the harness bundle.
• The harness changes direction during routing from main branch towards channels near injector connector, here as well Furr-tree clips are utilised.
  
  
  

Mounting of plastic guiding channel

• Plastic guiding channel is best option for proper and easy routing of the wiring harness near the injector-connector area, since there are eight connectors present. It will reduce the complex wiring harness routing. Two guiding channels are utilised for both right and left side of the engine.
  
  

Defining Branch Points

• Keeping a minimum distance of 55mm between branch points, convenient points are added on to the main harness branch to route the harness over to pressure sensor-connector, Coolant temperature-connector, neutral transmission connector and speed sensor-connector.
• From the entry side of the guiding channel, we have created first branch point at 130mm and then subsequently created seven branch points at 65mm each.

Adding protective coverings to harness bundle

• To provided protection for wiring harness, corrugated tubes are utilised as coverings. For 15mm bundle segment 20mm Cot tubes, for 10mm bundle segments 15mm cot tubes, for 5mm bundle segments 10mm Cot tubes are utilised.
• A minimum clearance of 20mm is provided near each connector-bundle entry point.

Checking bundle continuity

• Go to Edit>Search>Workbench-Electrical>Type-Bundle segment>Attribute-fully connected.

A pop-up window will open, in that selecting True option will show all the connected bundle segments while selecting False option will show all the non-connected bundle segments.
In the false option, there are Zero bundle segments. Hence all bundle segments are connected.

Here, we have selected for the 'True' option and searched for results. All the bundle segments are highlighted found showing that all the bundle segments are electrically connected as shown in below figure.

Wiring Harness Flattening

Defining Harness Flattening parameters

• A new Product file is created inside the Electrical Harness Flattening workbench.
• Next, we should define the harness flattening parameters by clicking on its respective icon. And necessary settings are changed.
• It is recommended to have single line representation for bundle segment and double line representation for protective coverings, for easy differentiation.

Flattening of the harness

• To flatten the harness, the flattening plane must be selected by selecting a reference face from any connector and all the harness branches present in the assembly.
• Once it is flattened, by using rotate command, the bundle segments can be rotated, bent as per our requirement for easy arrangement on the drawing sheet.
  
  

Creating 2-D drawing of the Wiring Harness

• We should insert the front view of the wiring harness into the drawing file as shown below.
• In the view tab of properties pop up window of the front view, 3D wireframe should be always "visible". If this setting is not selected the bundle segments will not be visible in the drawing view.
  
  
  

Drawing Sheet Features

A typical/simple Wiring Harness Flattening drawing must have

• Front view of the Wiring Harness Assembly
• Bill of Material table in the bottom
• Frame and Title block
• Corrugated and Wiring harness connection data tables

Bill of materials

Conclusion:

In this way, we have routed wiring harness for a V16 Engine. Also, prepared flatten view drawing for the same.