Challenge

Project 1

KKondapparajan N6 Feb 2023

AIM:

Route the wiring harness on given V-16 engine and prepare flatten view in CATIA. Apply all packaging rules and industry best practices.

Theory :

The given V-16 engine consist of following electrical components to which harness routing is required.

8+8 fuel injectors on the engine cylinders for both sides of the engine block (16 injectors), which are connected by a 4 pole connector with the wiring harness.

2 camshaft sensors on each engine block (4 camshaft sensors), which are connected by a 4 pole connector with the wiring harness.

Engine coolant sensor at the centre of the engine between the two blocks, which is connected by a 2 pole connector, with the wiring harness.

Engine oil temperature and pressure sensor fitted at the oil sump of the engine on both engine cylinder blocks, which are connected by a 2 pole connector with the wiring harness.

1 sensor to measure vehicle speed, which is connected by a 2 pole connector, with the wiring harness.

1 sensor to sense neutral position of the transmission assembly, which is connected by a 2 pole connector, with the wiring harness.

An interconnection connector to connect engine harness system to vehicle harness system.

Other equipment's required to complete the wiring harness routing

Guiding channels to protect the harness routing from high heat zones of the engine wherever necessary.

P-clamps to provide positive clamping and ensure clearance management for the routing wherever necessary.

Sheet-metal brackets such as L-clips to mount the interconnection connector.

Mounting clips to mount the connectors whenever required.

Corrugated protection tubes to protect the wiring harness.

Assumptions and packing rules :

Wiring harness routing shall provide ease in manufacturing, accessibility, easy removal and easy maintenance of attached equipment's and routing harness.

Wiring harness should be routed in such a way that it is easy to assemble on a vehicle.

Wiring harness should be kept away from sharp environments like sheet metal brackets, panel edges, corners etc.

Avoid harness routing and clipping in blind zone of operator during harness during installation.

Ensure that routing meets the clearance requirements with the different surrounding parts.

Routing shall provide enough slack for each branch to avoid additional stress on wire and terminal crimping joints but ensure that extra slack does not cause wiring harness foul with surrounding parts and impact desired clearance requirements.

Enough clamps should be provided to ensure the positive clearance with surrounding and safety of wiring harness.

Use of plastic guided channels are recommended to meet the clearances in critical areas if it is difficult to achieve by use of clamps.

Branch length should be minimum 50mm.

Minimum distance between clip and nearest branching point should be 25mm.

Minimum distance between two breakouts should be 50mm.

Limit the no. of branches from single branch point to 4.

Ensure that harness protection is provided according to surrounding temperature, manufacturabilty and expected reliability.

The min. bend radius is to be 1.4.

Consider min 5% slack in the wiring harness if needed.

STEPS INVOLVED IN DEFINING CONNECTORS:

Defining electrical properties to the normal connector.
Creating two points at the first mating face on both side of the connector,one is connector connection point and the other is bundle connection point.
Create axis system at the connector connection point for defining the connector.

Defining the connector bundle connection point.the same procedure is repeated for all the remaining connectors

Create a new geometrical bundle,copy and paste the individual connector of different family and manipulate according to the engine.

Adding P-clamps to provide positive clamping for the wiring harness.

P-clamps should be defined with electrical properties before inserting into the geometrical bundle assembly.

First define geometrical parameters such as entry point, entry plane, exit point, exit plane and base plane as shown in the image below.

STEPS:

Create two points at each end as entry and exit point

Create two planes at each end as entry and exit plane.

Create base plane:

Click on support definition - select part - select one entry point & select entry plane with respect to that point, exit and base plane.

Do vice versa(Click on support definition - select part - select another one entry point & select entry plane with respect to that point, here now exit plane selected and then select base plane.)

Adding guiding channels

The given V-16 engine has 8 injectors both on the left and right side of the engine which are close to one another, hence using plastic guiding channels is the best option for easy and proper routing of the wiring harness and maintain clearance requirement of the wires from the high temperature parts of the engines.

Before adding guiding channels into the geometrical bundle assembly it is necessary to define electrical properties to it, which is done by following steps.

First create geometrical parameters such as bundle entry points, and external reference line in the part design workbench to route the wiring harness into the guiding channel as shown below.

Defining geometrical parameters for guiding channels

Go to electrical part design and define the part as equipment using equipment command and define bundle connection points using bundle connection point command towards the entry points of the guiding channel as shown in the image below.