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PAGE 2 FIVE QUESTIONS TO ASK YOURSELF WHEN MEASURING OVER 50 G TE CONNECTIVITY SENSORS /// FIVE QUESTIONS TO ASK YOURSELF WHEN MEASURING OVER 50 G QUESTION 1: WHAT IS THE EXPECTED DYNAMIC RANGE YOU WILL BE MEASURING OR TESTING? Results of high g-force tests can be difficult to predict—and determining the necessary full-scale range of the sensor may require some careful consideration When using an accelerometer, you want to give yourself enough of a margin to ensure your test results are useable and the measurement range does not exceed the FS output of the accelerometer. If you don't, and your g-force is higher than your accelerometer's upper limits, you may end up clipping your signal and render your test results useless. By best practice standards, you'll want to plan for your results to fall within 30-40% of the device's full-scale range, and never less than 10%. If you run too low, your measurement resolution could be compromised. QUESTION 2: WHAT IS THE MEASUREMENT BANDWIDTH? The measurement bandwidth you choose will depend on many factors, specifically the type of test and the impact surface. If you're looking to measure a drop on a soft landing, for instance, a narrow bandwidth may be fine. But if you're looking to measure peak g's in high-impact tests, like munitions and automotive crashes, you'll need a wider bandwidth. And that's where impact surface begins to play a role: If severe enough, high shock, metal-to-metal impacts can cause wider bandwidth accelerometers to break from resonance. To combat this problem, a damped accelerometer can be used to prevent ringing and deliver accurate measurements. WHAT IS THE EXPECTED DYNAMIC RANGE YOU WILL BE MEASURING OR TESTING? When using an accelerometer, you want to give yourself enough of a margin to ensure your test results are useable and the measurement range does not exceed the FS output of the accelerometer. If you don't, and your g-force is higher than your accelerometer's upper limits, you may end up clipping your signal and render your test results useless. By best practice standards, you'll want to plan for your results to fall within 30-40% of the device's full-scale range, and never less than 10%. The measurement bandwidth you choose will depend on many factors, specifically the type of test and the impact surface. If you're looking to measure a drop on a soft landing, for instance, a narrow bandwidth may be fine. But if you're looking to measure peak g's in high-impact tests, like munitions and automotive crashes, you'll need a wider bandwidth. WHAT'S THE MEASUREMENT BANDWIDTH? B TEST A TEST It's also important to know how you'll install the accelerometer, as well as where you'll place it. For best results, accelerometers should be mounted rigidly to the apparatus. And while there are some materials, like cyanoacrylate that can be used to adhere an accelerometer to a device, most epoxies and glues should be avoided, as they'll serve as extra dampening agents and absorb energy before it can be registered by the accelerometer. HOW WILL YOU MOUNT THE SENSOR DURING TESTING? IN WHAT CONDITIONS WILL YOU BE CONDUCTING YOUR TEST? WHAT IS THE EXPECTED DYNAMIC YOU WILL BE MEASURING OR When using an accelerometer, you want to give yourself enough of a margin to ensure your test results are useable and the measurement range does not exceed the FS output of the accelerometer. If you don't, and your g-force is higher than your accelerometer's upper limits, you may end up clipping your signal and render your test results useless. By best practice standards, you'll want to plan for your the device's full-scale range, and never less than 10%. The measurement will depend the type If you're landing, may be peak g's and automotive bandwidth. WHAT'S THE MEASUREMENT BANDWIDTH? B TEST A TEST It's also important to know how you'll install the accelerometer, place it. For best results, accelerometers should be mounted rigidly to the apparatus. And while there are some materials, like cyanoacrylate that can be used to adhere an accelerometer to a device, most epoxies and glues should be avoided, as they'll serve as extra dampening agents and absorb energy before it can be registered by the accelerometer. HOW WILL YOU MOUNT THE DURING TESTING? IN WHAT CONDITIONS WILL CONDUCTING YOUR TEST?

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