Quality Control: How to Test a Custom Cable Assembly

Leading Custom Cable Manufacturer | Meridian Cable

Custom cable assemblies can be fairly complex; with branches of connectors, terminations, and specialty components made just for the task at hand. The same sophisticated system that can help power industrial control systems, advanced medical instruments, and even a fighter jet, is only as good as each and every component that goes into the system. With Meridian, this requires some next-level testing techniques. 

Here, we’ll highlight all the steps of a cable assembly inspection checklist and the many ways our design team ensures our products are tested and retested for continuity, integrity, polarity and functionality before they’re ever shipped.

What Testing Looks Like for Custom Cable Manufacturers

When a custom cable assembly is being developed, it will have to undergo many different rounds of testing. This could be electrical in nature, or in relation to the mechanical appurtenances, environmental variables, or any number of different testing techniques for the purpose of validating the integrity of the design. 

With a successful test, our design engineers know that the critical components meet their intended ranges. It is not until all the different qualifications-based testing is complete, that volume manufacturing will be undertaken. Many products will require more testing both within the manufacturing process, and once complete, to make absolutely certain the cable assembly components are performing in range. 

The design team are true masters of knowing the perfect tests to perform to ensure the product works as it should. Tests can take time and need to be factored into a rock-solid project schedule to ensure the custom cable assembly project remains on-time and on-budget from start to finish. Any design-build custom cable assembly manufacturer worth their weight should have a stringent cable and harness inspection checklist in place.

How to Test a Custom Cable Assembly for Continuity

Cable assemblies essentially connect one device to another in an electrical system. Therefore, an electrical continuity test to ensure this function is both basic and crucial. A test for electrical continuity makes certain that the wires and connectors have been assembled correctly because there is an electrical current flowing. Measuring for the electrical resistance and for a free-flowing electrical connection helps our design engineers spot any points where a conductor and/or wire may be damaged or otherwise impeding the flow. 

For this test, we get to use some pretty cool equipment like a multimeter device. This little electrical testing machine applies voltage to the portion of the cable assembly being tested to get an accurate measure of the resistance being faced. Even cooler, often we’ll be able to set up this test in an automated system so that we can test multiple branches of the custom cable assembly at one time. For a custom product, this can create some high-level tweaks to design a testing procedure that accurately measures all of the benchmarks the assembly needs to hit in order to roll off the assembly line with our engineers’ mark of approval.

Another electrical test our in-house engineers employ is called a high potential (HIPOT) or high voltage test. HIPOT testing involves making certain that the insulating jacket in the cable contains no defects in its design or some other form of degradation. By using a very high voltage between two conductors in the assembly, a large amount of stress is placed on the insulating materials and connectors. If the connectors can all withstand the effects of having high voltage shot through them for a specific time frame, it is a good indicator the unit will perform well under normal conditions.

Testing Custom Cable Assemblies for Integrity

custom-cable

Structural integrity is absolutely crucial for any cable assembly, as it’s going to have to perform its duties under real-world conditions, not just in our manufacturing facilities. There are a wide number of different tests that can be used to help design staff know the relative strength of the cable assembly and its ability to resist things like fatigue and abrasion. 

Two mechanical integrity tests that are standard for custom cable assembly manufacturers include a pull test and a flex test.

  • Pull Test – this helps our design team see the points of failure for the wires, connectors, and other components in the system. With a measured approach, we can know the exact weight load that the system’s architecture can withstand. This is especially useful when a client has a specific load in mind e.g. the cable assembly must be able to stand up to no less than 50 pounds of tension without its integrity being compromised. There are several variations on the pull test that can be run to achieve the desired computation. For example a pull and break, as it sounds, tests the components to failure where, conversely, a pull and hold tests the components being held at a constant rate for a specific period of time. The pull test can involve sophisticated automated testing units or can be as simple as a cable assembly with a weight attached.
  • Flex Test – thinking of a cable assembly being employed in its intended environment, the components are going to be twisted and bent in all manner of different ways as it is fitted within the structure of the overall product such as inside an automobile. The cable assembly doesn’t just naturally have the ability to flex for a lifetime without breaking, it’s a very specific engineering consideration of the design process. Hence, the necessity of performing a flex test with just about every custom cable assembly that’s ever produced. Special flexural strength machines can be used to evaluate the assembly’s durability while being flexed and bent to ensure the components – the jackets, sleeves, and other materials – are the right combination for the assembly’s intended environment.

Whatever test is used, our design engineers employ the right steps of a mechanical integrity test in order to ensure the unit is absolutely solid before it ever reaches the client and can withstand exactly what’s being asked of it cycle after cycle. 

How to Perform a Harness Inspection Checklist for Polarity

Polarity configuration is important to be able to test before a cable assembly is ready to be employed. Typical polarities in cable assembly manufacturing run “a”, “b”, and “c”, each with their own specifications. With the evolution of new components, so comes the evolution of new testing techniques. Some of the sophisticated testing units we use can perform simultaneous checks at once such as a polarity check and a continuity check. This helps save time and keeps the project on schedule.

How we Test a Cable Assembly for Functionality

How the unit will perform in the field is arguably one of the most important tests we can do to ensure the unit meets the standards it needs to. To do this, we designed our very own advanced life testing lab where our design engineers get to throw all manner of different environmental factors at an assembly and measure how it responds to certain variables. The custom cable assembly may be subject to incredibly harsh conditions, especially when employed by our men and women in the military, so the components need to be able to withstand these. 

Some of the tests our design team will look at during this phase can include:

  • Extreme temperatures
  • Airtight/Watertight 
  • Salt water corrosion
  • Chemical resistance

For many components, these tests aren’t nice “options” to add onto your order, they are absolutely critical for the success of the system. Whether the application is medical, military, telecommunications, or some other critical function, we know our clients rely on the custom cable assembly our team produces which is why we subject the components to so many different environmental factors. This helps the design team spot any weaknesses that need to be tweaked and mitigated against. 

How we Test a Cable Assembly for all the above

Many times a cable assembly must be tested for continuity, polarity, integrity, hi-pot and for any embedded components such as resistors, capacitors or diodes.  While it is possible to test each parameter as described above, that could be a lengthy process, not cost effective and possibly miss something.

When an assembly requires these multiple levels of testing it is best to use an automated, computerized tester.  Here at Meridian we use Cirrus testers.  Our engineers create a “golden sample” that is tested by hand using various methods.  Once the “golden sample” is confirmed it is used to program the computerized tester.  Once programmed the tester can be used to test all the remaining assemblies, and do so much quicker.

Getting a Product Certified Through UL

With decades of experience as a custom cable assembly manufacturer of distinction and holding status as a UL-approved production facility, our team is quite gifted at helping get a client’s product certified through UL. We’ll help develop a sample that’s ready to be tested and UL’s design team will then put the components through their paces with a battery of testing to make sure it meets OSHA, ANSI, and other standards. Once a product meets all of the criteria, UL will issue a certificate that lets a UL-logo be placed on the products that are manufactured. That UL logo is recognized worldwide as a product that’s known to have been tested for safety and functionality. Not stopping there, our team can assist with the periodic audits UL performs, in place to ensure the continued adherence to UL standards.

Start Your Custom Cable Assembly Project Now

Our design engineers are gifted professionals, well-versed in designing the perfect testing parameters to ensure your product meets everything you’ll need it to do, safely and securely for the lifespan of the system. We take great pride in developing a comprehensive testing program that ensures each and every product off our assembly line has been tested until it has been made certain that it will perform as intended. 

Ready for a whole new experience with your custom cable design project? Contact our team now to get started.