Coaching children’s recreational league basketball when my kids were growing up was very rewarding—even if it was more like herding cats than playing actual basketball. There is one thing that stands out in my mind, however, and that was when a play worked the way we designed it. We first diagramed the play out for the kids, and then we practiced it until they understood the moves. When it finally came together in a game, it was a beautiful thing to see.

Today, as I work with wire harnesses that are built for electronic devices, I am reminded of those days coaching the kids on how to put the play together. First, the wire harness specifications are drawn up in the same way we would diagram the play. Then, the harness is meticulously laid out, just as we demonstrated to the kids how to execute the play. There’s a lot more to the process of course, and thankfully, the wire harnesses usually don’t talk back to us. Here are more details of the PCB wiring harness manufacturing process that your contract manufacturer should go through when building your assemblies.

Input: What Your CM Needs for the Wire Harness Manufacturing Process

Contract manufacturers often build both flat ribbon cable assemblies and wire harnesses. To distinguish between the two, a multicore cable assembly is an external connection to devices and will have different environmental considerations, such as their thickness, insulation type, and flexibility. A wire harness, on the other hand, will provide the connectivity between systems in an electromechanical assembly, such as connecting a power supply to a motherboard.

Wire harnesses are laid out and built on a panel that has pegs positioned strategically where the wires will branch out into different directions, or connectors need to be added. This way, the harness is laid out to the exact dimensions that are required. Usually, you specify these dimensions, and contract manufacturers are used to getting a wide range of information to work with. The information can be something as simple as a hand-drawn note, or a series of complex 3D CAD models, as well as everything in between.

However, as with anything that is manufactured, the more detailed documentation and precise specifications you can provide, the fewer problems there will be on the assembly floor. Here is a sampling of the data that will best help your contract manufacturer when building your wire harness: