The four reliability tests you need to know
Reliability tests come in all shapes and stripes. One of the tricks of conducting a good testing process is choosing which tests to use and in what order. Today, we’ll give you a quick rundown of the types of tests you should consider when designing your test process.
While this list isn’t comprehensive, here’s a selection of types of tests you might use, and when they’re called for.
- Thermal tests. This test helps you understand if a product will function in the environmental operating range you expect — hot, cold or humid climates. We recommend a basic thermal test regardless of what the product is.
- Mechanical tests. Mechanical tests measure a product’s mechanical ability to function even when under stress. There are a few categories of this:
- Squeeze or Pressure. How much pressure can your product withstand? If it’s put in a user’s back pocket and he sits down, will the product survive, or will it be damaged?
- Granite test. A pretty standard test is called the one-meter granite drop. Be careful here not to design the test to pass — test it at angles that are representative of how the product would be held and dropped in real life.
- Repetitive drop testing. Here you drop a product over and over again. Also try the heavy set-down — throwing the product carelessly on a table or hard surface. This can uncover connectors that could pop, glass breakage or materials shifting.
- Chemical tests. What chemicals will come into contact with your device on a regular basis? Sunscreen is particularly harsh on plastics and coatings — so if your product will be handled, make sure it’s resistant to the chemicals that might be on your users’ hands!
- Use case cycling. If your product plugs into a USB, make sure the connector can be plugged and unplugged as many times as you expect in the device’s lifetime. Button cycling makes sense, but beware of only testing in the lab. Make sure to validate your test in the real world so that you don’t miss out on unexpected use cases.
For all of these types of tests, you’ll want to consider whether it’s more appropriate to do use case testing or strife testing. Use case testing focuses on what’s expected from the real-world scenario whereas strife testing is about understanding how much a product can take before it will fail.
If you’d like to see how these tests can be organized and carried out in real life, check out Instrumental’s Reliability Test Kit, which gives test definitions and setup instructions for cable accessories, part level plastic enclosure testing and a fictional IOT home device. You’ll also find detailed test definition, setup, and instructions for a wide variety of reliability tests.
At any rate, remember to choose your tests wisely. Our test kit can help you figure out how to do that, but an early step is to understand your menu of options. We’ll be writing in the next few days about how to design an efficient reliability test procedure, so stay tuned.