Does your cable assembly manufacturer have these quality control measures in place?


Uninterrupted service is critical for your equipment. So it follows that quality is a key performance metric for the custom cable assemblies inside the machinery.

If a cable fails, you risk:

  • Spending extra man hours for redesigning prototypes
  • Forcing equipment to operate blind
  • Adding hours of troubleshooting time from a highly paid technician
  • Damaging the customer relationship

The question then follows: How can you be certain you’re getting quality cable assemblies?

After all, every manufacturer that you work with will say they put quality above everything. But when it comes to quality, showing resonates much more than telling.

In this article, we’ll walk through key questions to ask when evaluating your custom cabling partner, touching on topics such as building to IPC/WHMA-A-620 standards, ISO 9001 documentation and production checkpoints. By the time you’re finished, you’ll have the tools to make a confident selection of a quality-focused manufacturer. 

What are the industry standards for cable quality?

Inspection against IPC/WHMA-A-620 standards are considered standard for the industry.

There are three quality classes used in this standard:

  • Class I is the least stringent and is appropriate for inexpensive consumer goods. 
  • Class II is appropriate for machinery and equipment where uninterrupted service is desired. 
  • Class III is the most stringent and is appropriate for applications where the functionality of the cable is critical, where failure may result in loss of life. 

As you and your team work on your cable assembly design, get familiar with the three classes to find the best tradeoff between cost and quality. That way, you can specify to your manufacturer which class standard you would like your cables to be built against. For example, at Multi-Tek our default is to build against Class II standards.

Additionally, make sure your manufacturer works with IPC/WHMA-A-620 certified assemblers and look for the logo (above) on their site. This will show you that their team is committed to following industry-proven standards and knows how to implement them in manufacturing processes.

Ask your manufacturer if they have these measures in place

This isn’t to say you need to do an ISO-level audit yourself. Rather, the answers to these questions — robust or not-so-robust — will paint a clear picture of your manufacturer’s quality assurance program.

Are you ISO certified — and how does your team stay up-to-date?

When a manufacturer is ISO 9001:2015 certified, that means all processes are documented. Their team has standards to refer to for every aspect for production — from production to assembly to inspection.

To take it further, ask how this documentation plays a role in the day-to-day production work. Are there revision-controlled drawings to maintain consistency after design changes? Are approved photos of validated first articles used to ensure that each cable is built exactly the same way? Is information stored and accessible, such as assembly work steps and shipping records?

Whichever way this information is organized (at Multi-Tek, it’s all stored in our proprietary Cable Tracker software), this shows you that ISO documentation is an active part of production.

What checkpoints are in place for pre-production?

These will likely vary from manufacturer to manufacturer. But there are some basic checkpoints in which errors can be caught (and fixed) so your cables are built exactly as you designed:

  • BOM verification: Does the cable manufacturer’s BOM and the drawing BOM match?
  • RoHS compliance verification: Have all components been checked for RoHS compliance?
  • First article verification: Has a first article been approved prior to production quantity builds?
  • Drawing rev level verification: Do all procedures and documentation match the latest revision?
  • Cut list verification: Have the cut lengths been shown to result in a finished assembly of the correct dimensions?
  • Test setup verification: Has the first article test result data been checked against the drawing and locked from future modification?
  • Previous build notes verification: Have any design improvement opportunities discovered during the first article build process been communicated to the customer?

These measures greatly reduce the possibility of errors by stopping them before they have a chance to show up on the production floor.

What testing takes place during and after production?

To illustrate what this can look like, here’s a few measures we have in place at Multi-Tek:

  • As soon as wire and cable has been cut and crimp termination has begun, a supervisor checks all lengths, performs a visual inspection of crimp terminations, and verifies by micrometer measurement that all crimp heights are to spec for the terminal and wire gauge. 
  • After cutting and termination is complete, the first article is tested (even if the cable has been built many times in the past).
  • Cables are tested for 100% functionality testing regardless of IPC Class (as opposed to sampling-based testing programs that some manufacturers opt into for reducing cost).

Frequent testing helps catch any faulty or incorrectly built cables before they reach your facility.

How do you ensure consistency between builds?

When a cable assembler comes across a drawing, it must be interpreted by that individual. Occasionally, there will be more than one way to interpret a requirement; a drawing is a set of requirements, not instructions on how to build the cable.

This can lead to a lack of consistency — and your manufacturer should have steps in place prevent it.

For example, the dimension shown on the drawing is rarely the length the wire and cable needs to be cut in order to achieve the correct finished length. To standardize the interpretation, some manufacturers will produce a cut list that gives assembles precise cut dimensions and tells them exactly which tools should be used. This cut list is a controlled document and ensure that regardless of the amount of time that passes between builds, you can count on a consistent product.

Can you offer feedback on my design?

This might not seem directly related to quality assurance measures, but the response can tell you a lot about your potential cabling partner.

As you and your engineered team evaluate cable assembly partners, be wary of a supplier that returns a quote without asking any questions or providing any feedback on the design. This may indicate a supplier that doesn’t have a well-developed quality management system and isn’t committed to achieving a cable design that meets 100% of your needs.

Still have questions about cable assembly production practices?

We’ve outlined high level topics relating to quality control during manufacturing. But you may still have concerns about what these measures look like in practice for your custom cable assembly.

We can help with that.

After you submit a quote, a cabling expert with reach out within an hour or two to learn more about your project and talk through what production (and quality control) will look like for your project.