With the rising popularity and use of the automobile over a hundred years ago, the need for a system of interconnecting highways throughout the United States was recognized. What started as the Federal Aid Road Act of 1916 eventually ended up as the Federal Aid Highway Act of 1956, or more commonly known as the Interstate Highway System. Combining some older highways with newer construction, the interstate system connects population centers throughout the United States with highways that are designed for high-speed traffic. Whether you are traveling from North to South or East to West, there is usually an interstate available that will make your trip more direct.
In the same way, electronic devices also need to interconnect their different components. Circuit boards, control panels, displays, and other I/O components must be directly connected just as I-80 connects San Francisco California to Teaneck New Jersey. Doing this requires a wire harness that is precisely made for the system that it will be installed in. These connectors can range in size from two short wires twisted together to connect a fan to a circuit board to a very large and complex wire harness that interconnects all of the different components in a large mainframe chassis. Here are some considerations you should be aware of when working with a contract manufacturer to have a wire harness and cable assembly built.
Wire Harness and Cable Assembly: How They are Built
First of all, let’s put a name to what we are talking about. A wire harness is designed to interconnect a system, or box build, and it is internal to that system. It usually consists of multiple wires bundled together and will branch out in different directions with multiple connection points.
A cable, on the other hand, is external and will be used to connect between different systems. A cable’s insulation type, thickness, and labeling will be specifically designed for the environment it is used in.
To build either of these, your contract manufacturer will likely follow these steps:
- Review build documentation: Your CM will review your specifications and your bill of materials (BOM). They will also research alternative parts if necessary to replace unavailable parts that may be in your BOM.
- Procure materials and components: Next, the materials and parts for your build will be purchased. This will also include the parts necessary to test the final product once it is built.
- Create manufacturing instructions: Working from the incoming documentation, the CM will prepare internal build and testing steps for the factory. These documents will include illustrations and examples.
- Build the wire harness or cable assembly: Now the wire harness or cable assembly is ready to be built.
- Test: Once the product is complete, a complete series of tests will be done to check continuity and fit within the system.
Your CM will document all phases of the manufacturing of your wire harness or cable assembly from build instructions to test procedures. However, all of this preparation is only as good as the input you supply to them. Here are some of the data that your CM needs to successfully build your product.
What a Contract Manufacturer Needs from You for a Successful Build
Wire harness and cable assembly by VSE.
When you choose a CM with a lot of experience building wire harnesses and cable assemblies, they are used to working from a wide variety of data. These contract manufacturers have likely worked from everything from simple “napkin” sketches to precise 3D CAD models and schematics.
To help with a speedy and high-quality build of your product, however, it is important that you clarify all critical features and specifications at the beginning of the project. This will prevent delays that could occur if the CM has to go back to you for missing or unclear data. Your input should also include any unique insights that were gathered during the product’s prototype process.
Another key consideration for success is to make sure that you work early with your CM on the development of your product. This way, the CM can help you to select components that are readily available and at a lower cost whenever possible.
You will also want to make sure to follow the component manufacturers’ recommendations in your specifications. For instance, be sure to use the termination type recommended by the manufacturer of components that will have wires attached in your specifications. Also, specify the component manufacturers’ recommended torque values for critically threaded electrical fasteners. This becomes extremely important for fasteners that are molded into a plastic housing as opposed to bolting two pieces of sheet metal together.
The Advantages of Using a Local PCBA Contract Manufacturer for the Job
The cabling between systems and their interconnecting wire harnesses are often the last parts of the system to be designed. As such, it is not unusual that they have short design cycles to meet critical deadlines. Here is where using a local contract manufacturer can really help. Instead of wading through a sea of red tape working with large manufacturers that are far away, a local CM will give you immediate access to the help you need. Changes can be made quickly, and you can be more directly involved.
Another advantage of a local CM is that they are more likely to know you, your business, and what is important in your design. When working with large capital equipment that has hundreds of interconnects, it is common for mislabeled wires, poor terminations, and improperly seated contacts to be the root cause of 80% of the system-level troubleshooting. Working with a local CM who knows you and your needs means that your designs will get the proper preparation, manufacturing, reviews, testing, and installation in the final system. With this level of attention to your project, you can trust that you will end up with superior results.
At VSE, we have been building cable assemblies and wire harnesses for three decades now, giving us the experience you are looking for. In all of our work, we go beyond the minimum requirements when building your products:
- We do more than simple continuity testing, we also test for marginal crimps and contacts that are not fully seated with their mating connectors.
- We track results by individual assemblies through labeled barcodes that are linked to that specific product’s test results.
- Together with our PCBA and box build assemblies, we can give you a complete electronics manufacturing service with much quicker and better results than using multiple vendors.
