The difference between a cable assembly and a wire harness


The terms “cable assembly” and “wire harness” are often used interchangeably, but they aren’t separate terms for the same product. They are unique products with entirely distinct manufacturing processes, and sourcing cable assemblies from a specialized wire harness manufacturer (or vice versa) will invite some struggles.

Knowing the difference between a cable assembly and wire harness can help you understand your manufacturing needs and guide your search for a right-fit supplier. For more details on custom cable assemblies in particular, read our manufacturer’s guide to custom cable.

Physical differences between cable assemblies and wire harnesses

The primary physical difference between a cable assembly and wire harness comes down to the complexity of their layout. Cable assemblies are typically point-to-point, single connector cables which sometimes include loopbacks or multiple legs but don’t involve any advanced layout.

custom cable assembly order

Wire harnesses, on the other hand, are designed to allow for simple assembly of large, multi-faceted wiring systems. Their defining feature is their complex arrangement of many wires and cables. They are useful in situations where installation of many separate cables would prove troublesome.

Since the wire harness is typically routed on a board by the manufacturer, the installer doesn’t have to route the individual wires on a crowded manufacturing floor. They remove the board and install the wires, which are already laid out in their proper arrangement.

Other than their arrangement and layout, there aren’t any significant differences between a cable assembly and wire harness. Both can perform the same functions and meet the same electrical specifications. But this simple difference leads to unique manufacturing processes.

wire harness layout at MTI

Different products require different manufacturing processes

Cable assemblies and wire harnesses require significantly different manufacturing processes with unique challenges, especially at high volumes. And the implications of these different processes influence the market for suppliers.

Cable assemblies are produced by connecting cable to terminals on their ends. To do this, suppliers specializing in cable assembly production use tooling tailored to the exact connections they’re making. The majority of the cable assembly process can be automated with advanced tooling.

For cable assemblies using discrete wire, a cut, strip, terminate (CST) machine is fed a long spool of wire and terminals on a reel. It cuts the wire to desired length, strips the insulation and crimps the connection in a few simple movements, no hand crimping necessary. Where multiconductor cable is used, automated equipment cuts the cable to length and removes the jacket before operators apply terminals with tabletop strip/crimp machines.

Some aspects of cable assembly production still need human hands, like tooling setup, hand soldering, terminal plugging, heat shrink application, cable tie installation and labelling.

Wire harness production looks remarkably different from cable assembly production. The process of routing wire and cable onto the board must be performed by hand and can take a lot of time. Suppliers that specialize in wire harness production use assembly lines from companies like Schleuniger or Komax that move the harness boards from station to station along a line of human operators.

Each operator is responsible for routing up to a handful of wires, and when they’re done, they press a button to let the machine know. Once every operator on the line is finished, the machine moves the boards along to their next station, and the operators continue their assembly.

wire harness production line
This is a specialized wire harness production line.

When the harness is simple enough, the production of the individual wires can be automated like a cable assembly. But for complex harnesses, getting the wire lengths precisely right is challenging, and getting them wrong is costly. Most often, the wires are all cut and laid out on the board, then trimmed to precise length, stripped, crimped and plugged by hand.

Even if automation of individual wire production were possible, you would need a large workforce producing a high volume of wire harnesses quickly to justify acquiring a CST machine. Otherwise, it’d spend most of its time unused, waiting on the board layout process.

Cable assembly vs. wire harness manufacturers

If you’re looking for a cable assembly or wire harness manufacturer, you’re likely looking for different qualities in those suppliers. A best-fit cable assembly supplier will have the proper tooling and experience with your particular needs and application.

The most successful wire harness manufacturers have very specialized facilities and access to a large labor force. Since the wire harness manufacturing process requires so much space and labor, most facilities specializing in it don’t produce cable assemblies at all. Some cable assembly suppliers are capable of producing very simple wire harnesses efficiently but struggle with more complicated harnesses.

Multi-Tek’s capabilities

Multi-Tek specializes in custom cable assemblies. We produce most of our best work for OEM’s who need cables in their industrial equipment, but our work is also used in high-fidelity audio equipment, military communication gear and plenty of other applications.

While we produce some relatively straightforward wire harnesses for some customers, we aren’t tooled for volume production of complex wire harnesses and recommend seeking a specialist for those projects.

Feel free to read about who we help and how, as well as what we don’t do.

Looking for help with a custom cable assembly?

If you are searching for a custom cable assembly manufacturer, you need a partner with expertise in producing cables for your application and the in-house capabilities to meet your needs to a T.

So let us know what you need. If it’s not in our wheelhouse (like a complex wire harness), we’ll let you know. If you’re still in the design phase, we’d love to talk shop and specs.