Priding ourselves on our skills and knowledge across a complete range cable assembly capabilities, here our highly skilled, Senior Quality Control Technician, Faye Holder, shares her knowledge on Manual Electrical Testing Vs. Automated Electrical Testing.
If you’ve spent good time and money to produce your cable assemblies, then the next logical step might be to reach for the multimeter to ‘buzz’ them out. While many test technicians rely on this tried and tested approach, the manual method has its limitations, especially as builds become more complex or quality expectations increase. Therefore, a multimeter is best used to test simple assemblies, prototypes or box builds.
However, as the number of test points expand, so does the time and effort required to adequately test them manually, increasing inefficiency, inaccuracy and decreasing long-term value. This is why an automated solution, such as the kind offered by MK Test Systems, is so vital.
Manual Testing with a Multimeter
Traditionally, manual testing with a multimeter has been used to check the continuity (whether each test point is electrically connected to where it should be) and detect short circuits (whether the current is taking its intended path rather than a short cut). ‘Buzzing out’ has been a long-established method of checking the electrical integrity of simple assemblies and prototypes. However, this approach requires a technician to manually probe each test point by hand, which is time-consuming and labour-intensive, while also being prone to human error, especially if testing a complex harness or connectors with multiple pins.
The Hidden Costs of Manual Testing
This brings us to one of the main drawbacks of manual testing – the cost. While initially testing with a multimeter might seem like a cheap option, the costs can quickly stack up. Although this method requires less initial setup – all you have to do is switch the multimeter on, turn the dial to the correct setting, and away you go (this is great if you need to quickly check the continuity of a simple assembly), but the time starts to spiral the more pins you have to check. It can also be a physically difficult process to probe two ends of a cable at the same time, and so it often requires securing the connectors in a vice or even requiring an additional operator – all of this adds valuable time and cost onto the end of the quality process – and the costs aren’t just monetary.
No matter how experienced the test technician, it’s impossible for a human to be 100% accurate when testing hundreds or even thousands of test points – a moment’s loss of focus can lead to missed faults, which in turn can cause costly reworks and, perhaps, even worse – reputational damage. While another consideration when conducting manual testing is that there is no digital record or automated traceability and so test reports will have to be created by hand and physically stored.
Automated Testing
The alternative to manual testing is of course to automate the process. This on face value seems like a costly option, and while there is the upfront investment of creating test leads and writing a test program, once these are in place, the process of testing is transformed from a lumbering, time-consuming chore at the end of production to a swift and streamlined operation.
For example, a fully populated 25-way D-sub connector on both ends of a cable will take between 3-5 minutes to ‘buzz out’ with a multimeter by hand, while those same connectors run through the Automeg automated tester will take 3-5 seconds (for continuity and short tests combined). So, while there is a little more work on the front end, after the automated test is created, you save minutes and even hours on the back end. And that set up time only applies to the first job, once the test leads and program are created, then the next time those cables are built, it’s simply a matter of loading the test program, plugging in the assemblies, running the program and saving the results.
Depending on the complexity of the assembly required, we may already have a test lead to fit your cables’ needs. For instance, we can test ribbon cable up to 64-pins and D-sub connectors up to 37-way (in any combination: male-to-male, female-to-female, male-to-female).
The automated program can check hundreds of connections automatically and perfectly every time and produce traceable test reports that can be tied to each individual assembly. An automated test system ensures consistent and repeatable testing without relying on the potential fallibility of an operator. Instead, a test technician can run multiple tests a day, increasing the speed of testing and reducing bottlenecks that can occur at quality control.
Customisable Parameters
Furthermore, automated testing allows greater flexibility in the test itself. You can specify what criteria you want your assemblies tested to, for instance a common test specification is the following:
- Continuity – 30V (Volts), 1A (Amp), Resistance 5Ω (Ohms)
- Short Circuit – 30V, 1A
- Insulation – 250V, 300MΩ (Megaohms)
Automated testing allows for customisable parameters – and as you can see, you can define resistance thresholds, insulation values and voltage tolerances, and then later easily up-rev, if needed. This level of control means that each assembly can demonstrably adhere to specific quality and industry compliance requirements.
Long-term Value: Precision and Productivity
Although manual testing works well for smaller jobs, and can also initially appear cheaper, automation quickly pays off in the savings made in labour hours, reduced testing errors, fewer returns and faster job turnaround, as well as adding value to audits and solidifying customer confidence.
If you’d like to hear more about how automated testing can help you, reach out to our sales team.
☎️ 01903 771336
📧 sales@klaceycables.co.uk
🌐 www.klaceycables.co.uk