Cable Assemblies vs. Wire Harnesses
There are many vital differences between related products; cable assemblies and wire harnesses, and the confusion about the matter is made worse due to how many people use the terms interchangeably. However, there are differences between each, and at Geospace Technologies, we strive to work on our helping the public become knowledgeable in the items we offer. Let’s look at the similarities between cable assemblies and wire harnesses before outlining the key differences between them.
Why Are Wire Harness & Cable Assemblies Often Confused?
One reason is that people often get wires and cables themselves confused. A wire is a narrow strand of material, typically copper, that conducts electricity. Cables have at least two wires, and they may have more than that. However, cables may contain conductors that aren’t copper wire; fiber optic cables are a perfect example of this. That means one of the significant differences between cable assemblies and wires harnesses is the wire/cables themselves.
Since cables are often bonded or brained together, they look like a group of intertwined wires — one reason why the terms are used interchangeably. Making matters worse, a wire harness may be called a wire assembly or cable harness.
Cable ties can be used in wire harnesses, too. Another reason the terms get confused is that a wire bundle can include a harness and a cable. The wires bundle together to keep the electrical connections organized and cables can be grouped like wire assemblies. What is the difference between the cable assembly and wire harnesses? Let’s look at some of the critical differences between cable assemblies and wire harnesses.
The Number of Terminations
A cable assembly is a length of cable with connectors on one or both ends. The most basic wire harness has three discrete components. However, a wire harness often has multiple ends running off in different directions, and there are several terminations on each branch. A cable assembly typically has just two ends. If there’s another connection that needs to be made in the same assembly, you buy and connect another cable.
The Standard Number of Layers of Insulation
Cables coated with one or more layers of insulation. The wire conductors in cables are, by definition, well-protected. Wires are generally only covered with a single layer of shrink-wrapped thermoplastic insulation. This makes them thinner and, on average, weaker. A wire harness typically can’t survive compression or severe wear and tear the way a cable assembly could; the harness assembly is just there to hold the wires together and, sometimes, in an assigned configuration. Wire harnesses are almost always intended for indoor use.
On the other hand, wires are lighter and more flexible. This allows wire harnesses a better choice for connecting things in a tight space or when weight is a concern. For example, wire harnesses will be used in aerospace applications over cable harnesses, if possible. Cables will be used in military and industrial applications where weight and space are not as important as durability and reliability.
The Overall Design Requirements
Most cable assemblies are designed for specific environmental factors. Temperature and humidity tolerance is one set of environmental factors. However, cable assemblies can be designed to fit in a given area, too. For example, cable assemblies for connecting devices have specific connectors on the ends, and the connecting cable may have to fit within specified dimensions. Wire assemblies may have to meet dimensional or environmental performance factors set by the manufacturer, but that’s not the same as cable standards like IEEE 1394. This is also why you hear about buried cables but not buried wires.
The Functionality They Provide
Cables can carry two or more strands in the same cable. This is why cables for use in electronics may carry both data and power. Alternatively, the cable could use multiple wires inside to move that much more data. Each wire has a single purpose, whether it is to carry electricity or data. A wire assembly may transmit power or data, but a single wire can’t provide multiple needs the way a single cable could.
For example, the conventional wires connecting your TV or clock to the power outlet can’t carry data. However, the cable connecting your smartphone to the USB plug on your computer could charge it even as data transferred between them.
Cost
How can wire harnesses offer a low-cost solution for wire organization? In general, wire harnesses are cheaper than cables. Individual wires themselves are less expensive than wires. There’s also less engineering required to design the wire harness since you don’t have to come up with a rugged protective outer layer to meet strict performance requirements. The lower initial engineering cost often extends to the connectors, as well. Furthermore, if a circuit board design changes, it isn’t difficult to add, remove, or swap out wires in the wiring harness to match the altered connection points called for in the new design.
A complicated wire harness may be difficult to weave together and connect to every component on a large circuit board. This can result in cost-shifting from purchase costs to installation costs. On the flip side, the wire harness installation can be adjusted as required. You can bend the wire to make it fit around a given obstacle, and you can replace individual wires in the harness when needed. It isn’t cost-effective to take the cable apart and try to replace copper or aluminum wire strands inside of it. If a cable is cracked and the wiring inside is damaged, you always have to replace the entire unit; this makes wiring harnesses a better choice for electronics and advanced networks that are continually changing and evolving. It is simply more cost-effective.
If you would like to learn more about our thoughts on cable assemblies vs. wire harnesses, don’t hesitate to reach out to the professionals at Geospace Technologies. Since 1980, we have stayed at the forefront of engineering and manufacturing innovation. Contact us or submit a form about your inquiry.