How to make a fast frequency measurement?

[sam B]

I want to measure the frequency of a signal @ 50Hz. Now I use the "Tone Measurements" Express VI, configurated to measure frequency. The problem is that I only get a sample each 100ms, although the period is 20ms. Even more, it would be better if I could measure the frequency much faster than each 20ms. Is this possible?

[demux]

Hello Sam,

It is possible to measure frequency much faster then every 20ms. Probably the problem in your case is related to how much samples you bring at which rate to the Tone Measurements express vi. If you want it to give out a new value every 20ms, it is necessary that you bring it a new block of data every 20ms.

Let's start with the code you have at this point and the type (frequency?) of the signal which you want to read. 

Kind Regards,

Wouter

NI Belgium