0
\$\begingroup\$

Can I know the sensitivity of a power frequency measurement unit?

I can not find it in the specifications sheet.

I do have, though, the accuracy of the unit (10 mHz)

Thanks in advance!!


Update : I am going to reformulate the question ,

I have a requirement in a project I am working on of a certain sensitivity in a frequency meter. I am trying to reach some providers but in none of their datasheet the sensitivity is explicitly mentioned. On the other hand, accuracy is.

My question then is ? Having an accuracy of 10 mHz implies to have a sensitivity of at least 10 mHz?

Thanks again :)

\$\endgroup\$
11
  • \$\begingroup\$ At a guess, 17. I'm being facetious. Your question is unanswerable because you have omitted the brand, model and link to the datasheet. Please hit the edit link and fix the question. \$\endgroup\$ – Transistor Aug 25 '20 at 22:07
  • \$\begingroup\$ Hi, unfortunately, due to confidentiality I am not sure I can forward or post here the full datasheet. I am going to try to reformulate the question: If the accuracy if 10 mHz, the sensitivity is at least 10 mHz? I have the measurement sensitivity as a requirement in a project I am working but I can not find it in any of the providers datasheets. So I am trying to understand if it is implicit \$\endgroup\$ – AND Aug 25 '20 at 22:16
  • 1
    \$\begingroup\$ "Sensitivity" and a frequency measurement don't go together well, and in your title you call it a "power frequency meter". Sensitivity to what? Power? That's not about frequency, then. \$\endgroup\$ – TimWescott Aug 25 '20 at 22:21
  • \$\begingroup\$ Hi, thanks for the help I can quote the requirements I got : " The sensitivity of frequency measurements must be better than +/-10 mHz." In another part of the document is also mentioned : "Unit sensitivity must not exceed 10 mHz. This means that the unit must respond to changes of 10 mHz." And I was mentioning a power frequency meter because all the units from the providers are PQ meters as well. But I am only interested on measuring the power grid frequency. \$\endgroup\$ – AND Aug 25 '20 at 22:29
  • 1
    \$\begingroup\$ You're still asking about "sensitivity" when you mean "precision". Why? \$\endgroup\$ – Transistor Aug 26 '20 at 11:54
0
\$\begingroup\$

The answer to your question, in spite of lack of information about your measuring device, is yes. You cannot measure frequency with an accuracy of 10 mHz unless you can resolve the frequency to at least that amount, preferably even better like in the range of 1-5 mHz. By the way, in engineering we generally use the term "resolution" to indicate how small a quantity a measuring device can display. Sensitivity is usually reserved for how small a signal a measuring device needs to provide its accuracy and resolution. Also note that accuracy and resolution are not the same. Many meters that provide lots of resolution, that is display many digits, do not necessarily have the accuracy commensurate with that resolution.

\$\endgroup\$
2
  • \$\begingroup\$ I don't think you write what you meant regarding sensitivity. Try "can detect" rather than "needs". \$\endgroup\$ – Transistor Aug 25 '20 at 22:46
  • \$\begingroup\$ Hi, thanks for the answer! Yes I am aware of the difference between accuracy and resolution, but it is always nice to clarify it, so thanks. And happy that you agree with my point: if the accuracy is 10 mHz (+/-) the measurement unit necessarily needs to react to signals of that magnitude. ( Please correct me if I am wrong ) \$\endgroup\$ – AND Aug 25 '20 at 23:07

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.