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Is it possible to use a load cell to measure a force that is vibrating? The idea is to measure that force that is getting into the load cell in a sweep of frequencies and vibration is NOT a noise. Since most of load cell characteristics indicate static conditions, I was doubting if load cell is not right for dynamic measurements. Alternatively, is there a special family or model of load cells that could work under vibrating conditions?

The frequency of interest is in the range of under 500 Hz ( or let's say 1K)

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  • $\begingroup$ What frequency? 10 hz? 10000 hz? $\endgroup$
    – Daniel K
    Oct 12 '20 at 12:07
  • $\begingroup$ The frequency of interest is in the range of under 500 Hz ( or let's say 1K) $\endgroup$ Oct 12 '20 at 12:12
  • $\begingroup$ I don't think this is an issue. If you using something like a micro controller, the data acquisition rate is much faster than 1KHz. What is the engineering problem you are trying to solve. $\endgroup$ Oct 12 '20 at 17:17
  • $\begingroup$ @user8055 Sure, you will measure something. The question is whether you will measure anything accurate enough to be useful. $\endgroup$
    – alephzero
    Oct 12 '20 at 17:23
  • $\begingroup$ People often use strain guages for this. Also, if you want to measure a 1kHz signal you'll need to sample at least at 2kHz and better at 4+kHz. $\endgroup$
    – Eric S
    Oct 12 '20 at 18:55
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The load cell specification should include the frequency response.

Bear in mind that the load cell itself is a dynamic system (e.g it can be modelled as a mass and spring) which may affect the dynamic response of the device under test.

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  • $\begingroup$ Thank you, but only the natural frequency is indicated in data sheet and is bigger than 75k hz. So the thing is when I remove the part connected to the load cell, I still have the strange readings on it. I can't reveal the whole problem due to nda, but I could say that any mass I'm connecting to the load cell and then apply the vibrating force I see more force than expected in above 400hz $\endgroup$ Oct 12 '20 at 18:25
  • $\begingroup$ It's dyter 1203v3 $\endgroup$ Oct 12 '20 at 18:28
  • $\begingroup$ A Dytran 1203v3 should have no issues reading 500 - 1000 Hz. When the nat frequency freq is given with no other information, it is safe to assume an undamped response, which means usable bandwidth is about 20% of the nat freq. So 16 - 17 kHz in your case. As alephzero pointed out, if you have a significant mass load, then the overall system nat frequency could be significantly less than 75kHz. $\endgroup$
    – Daniel K
    Oct 12 '20 at 22:47
  • $\begingroup$ One way to figure out what is happening would be to measure the frequency response curve of your system (with and without the component you are trying to measure). The "obvious" reason is that something is not as rigid as you would like it to be, but if you can't give us any information because of a NDA there is no way to guess what might be happening. $\endgroup$
    – alephzero
    Oct 12 '20 at 23:20
  • $\begingroup$ From the data sheet mass and stiffness of the 1203v3 its resonant frequency would be about 260kHz, so the data sheet value of ">75kHz" seems reasonable enough. $\endgroup$
    – alephzero
    Oct 12 '20 at 23:23

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