Wire harness is a grouping of cables, wires or small assemblies designed to transmit electrical power or signals and they’re practically in anything that moves.  Yes, that includes boats, automobiles, air planes, trains, and more. A normal wire harness includes at most three discreet components, while the more complex harnesses include a lot more wires and other potentially active and passive components.

In most cases, a wire harness is confused with a cable assembly; the major difference between these two is that a wire harness has many ends running off in multiple varied directions with many terminals on every branch, while a cable assembly has only two ends.

Wire Harness Assemblies

Cable harness assembly

Wire Harness Design

Cable harness assembly is basically meant to simplify the production of a larger component, and it is made based on the electrical and geometric needs of the equipment it is going to be installed in.

Wire harnesses are used mostly in the electronics industries, in the production of construction machines, industrial equipment, and automotive industries. They are also instrumental in the production of washing machines, dryers, and refrigerators.

Cable harness assembly simplifies the making of these larger components by combining wiring into one or several units. By joining the many cables, wires, and sub-assemblies into a harness, the installer remains with only one component to install. In other words, a wire harness makes the completed assembly more secured against the abrasion and vibration effects, and by contracting the wires into a bundle that is not flexible, it allows for optimized space usage.

Once the design is automated, the process of making a wire harness begins with the construction of a scheme that is used to make the production paperwork and the assembly board for the harness. The assembly board also called the pinboard is a full-size layout of the harness and displays all of the components and their respective locations. It also serves as the workbench for the harness. The wires required for the harness are supplied on an original reel and are cut to the required length and labeled of printed for identification. When the wires are cut to the perfect lengths, they are peeled to display the conductors that are not insulated and then fitted with the required terminals or a connector casing. After that, these wires and components are placed on the master board and clamped together by any necessary straps, cable lacing, cable ties, tapes, sleeves, and weaves of extruded string or a combination of any of the above.

In spite of the urge to increase in automation, Cable harness assembly generally continues to be done by hand due to the many varied processes involved.

Wire Harness Assembly Methodology

Below are among the wire harnessing assembly methods

· Installing the wires and the subassemblies on the pin board.

· Routing the wires and the subassemblies through the required sleeves.

· Putting wraps, tapes or ties specifically on any branch outs.

· Setting terminals onto wires mostly if many wires go to the same terminal.

It is hard to make the processes involved in building a wire harness automatic, especially when making a small size batch. The manual procedure still remains more cost effective compared to automation. However, knitting or pre-production of a harness can be automated in a way.

This would result in the steps listed below

· Cutting and distinguishing wires individually. (Cutting or stripping machine)

· Crimping terminals onto one or the two ends of the wire.

· Incomplete plugging of wires initially fitted with terminals into connector casing.

· Soldering of wire ends using the soldering machine.

· Wire twisting

Testing of Wire Harness

A test board is used when running the electrical functionality of a wire test. The board is pre-programmed using the required electrical components. Plug the complete harness into the test and run the tests individually or multiple times.

The importance of Cable Harnessing Assembly

Below are five of the major benefits of cable harness assembly.

Makes installation easy

Cable assemblies are made of many wires attached within one solid form. Mostly, the wires are coded with colors, according to their function. Along with the package, the color-code scheme makes it easier and time-saving to do a one-time process installation instead of installing many loose wires. Thanks to the clearness of the packaged wires, many users can afford to install their harness manually instead of hiring a professional.

Acts as Protective Shield

Another reason to use a harness is that it brings in extra protection from the environment. A lot of industries construct structures out in the elements. The cables they use need to be protected from tough circumstances like galvanisation, intense sunlight, and heat, rust from water and salt, vibrations among others. The structure keeps wires in position protecting them from moisture. When you are assembling an application outdoors, offshore or just in a vehicle, the assembly will serve as a protector.

Allows for customization

Wires function as the communicative elements of clips and routers, which are also a major part of the wire set up. They transfer signals within and to varied applications. Varied wires serve varied purposes in cable harness assembly; assemblies offer themselves for customization since you can choose which characteristic to integrate into your arrangement. The key to using a customized assembly is to realize what you need and choose a firm that will understand the surroundings which you will use your assembly.

Easy to Repair

Just like it is easy to install assemblies, they are as well placed for repairs in the future. With the packaging of many wires, it is easy for technicians to remove one harness without necessarily having to run the risk of disturbing other harnesses. If a harness is used to give structure to many wires, it directs the wires direction. These arrangements can be used as roadmaps for areas with problems, giving a clear picture of the wire’s location.

Wire Harnessing Can be Cost Effective

Wire assemblies are economical options for applications, as they sometimes come pre-assembled. With increased regular users, buyers can spend less cash while focusing their efforts on more specialized ones. Some of the parts can be pre-assembled in case customization is required. The easy installation and repairs of harnesses work to bring down costs since no labor is outsourced.

Sources used:

https://en.wikipedia.org/wiki/Cable_harness