Electric cable assemblies are found on medical products, military equipment, industrial controls and machinery, and all kinds of consumer electronics. Electric cables can be defined as cables that transmit control signals or information, or that supply low current power typically below 5 amps. Often the power is DC by sometimes it can be AC, but in either case for electronic cable assemblies the power is low.
Electric cable assemblies are used on a wide variety of equipment they often experience wide ranges of movement, or flexing. Regardless of how much movement the assembly experiences it is critical that it be designed correctly to withstand any flexing. This is important for two reasons. One, a failed cable assembly means the data or power stops and this can have bad consequences. Two, a wrong design can increase costs beyond what the application truly needs.
Some applications require a lot of flexural capability. Examples are medical cables, military cables or industrial control cables where failure is not an option or the equipment runs quickly for long periods of time. Other applications don’t flex much at all. Examples are vending machine cables, security cables or box build wire harnesses that are installed one time and never move again.
Flexural requirements for wire assemblies can range from 1, in the case of wire harnesses, to hundreds of thousand for industrial cables. Some products need hi-flex cables to ensure they never fail, which is the case for medical cable assemblies and military cable assemblies.
How many flexes a cable can withstand is a direct function of the materials used in construction and the process employed to make the product.
In regards to electronic cable assemblies, there are really only 3 types of materials in any cable or wire, metal, plastic and fillers.
- Typically the metal used is copper in some fashion. The copper can be bare, plated with another metal such as tin, or in some cases clad around another metal such as silver.
- The plastic can be any combination of polyvinyl chloride, PVC, polyethylene, PE, polyurethane, PU, or thermoplastic elastomer, TPE.
- Fillers are used to ensure the cable’s cross section is uniform in shape, whether round, oval or square a uniform cross section is critical.
At the heart of all cables and wires is metal, typically copper. Metal as we all know comes in many varieties and copper, for most applications, has the best attributes to make a cable or wire. As we also know most metals don’t like bending. This is especially true of larger pieces, which is why most electronic cable assemblies use stranded wires. This means to make a certain gauge conductor many smaller strands of copper are used. The amount of copper doesn’t change it is just spread across many conductors. As we all know small things bend easier than large things so a wire or cable made with a high strand count will have a long flex life than a wire or cable made with one conductor.
Around the conductors is most often plastic of some kind. We all experience and use plastic every day and the variety is quite amazing. From the rigid bodies of cell phones, to the semi flexible sides of a milk or water container, to soft pliability of a rubber band plastics used in custom cable assemblies come in even more varieties than copper. Some custom wire assemblies can accept very rigid constructions, but for custom electronic cable assemblies usually a high degree of flexing is required. For these applications it is best to use plastics capable of handling repeated bending. These can range from PVC all the way to PTFE.
Obviously with all these factors designing a custom electronic cable can range from simple to very complex, so finding a qualified cable and wire vendor is critical for many companies. Meridian Cable recently designed, manufactured and cycled a cable assembly to over 200,000 cycles without any failures. If you need custom electronic cable assemblies, Meridian Cable can design and manufacture just what you need. Contact us today for any custom cables needs or view some of our cable assembly designs.