Tachometer application and conection with DAQ

[alextroy]

iam very happy cos today
i success to use DAQ card from NI in my application at the faculty
now i can read ( acquire  ) data from an accelerometer attached to bearing housing in the rotating machine
then i analyze the signal and show the results in a spectrum data indicator
if any one can help me in my next application i will be very thanks
i want to connect  a Tachometer to the DAQ card in an input analog channel to read phase data
cos i want to make a balancing process with a Tachometer and two accelerometer
does any one in the NI know how to connect the Tachometer to the CARD to acquire signals respected to the reading of the two accelerometers
   

[preston_johnson]

look at this code:

http://zone.ni.com/devzone/cda/tut/p/id/4381 

[alextroy]

 sorry the link you put is no helpful
it offer from NI a non completed VI
there is an important sub vi was not there
so i try to use the application and press acquire bottom and nothing happen and then i start to write this topic here
if you can offer any help over there tell me plz 

[Neal M]

Hello alextroy,

Depending on what NI hardware you have (and what type of tachometer), you probably want to use one of our counter tasks to accomplish your goal.  Specifically a period task or a frequency task would be ideal.  You can also use an analog tachometer as well.  The trick is that you need a card that has a counter for the counter task or a hardware timed analog input for the analog tach. 

From your previous posts, it appears that you are using a USB-6008 which is static timed only.  The reason static timing will not work for us is that it's sampling is not very accurate in time (being software timed). The example we always use around here is if your virus scan kicks on, it can cause a change in your sampling rate because your CPU has more to do.  If you are measuring slow signals, this may not be a problem, but it is something you should consider.

The big thing it sounds like you are looking for is our Sound and Vibration Toolkit.  This is an addon to LabVIEW that has a ton of analysis VI's that sound perfect for your application.  It includes an entire folder of order analysis VI's that do order tracking and analysis as well as an entire folder of VI's for Tachometer Processing.

Below are a couple of links that should help you get started with programming as well.  Please let me know if you have any questions.

DAQ Getting Started Guide

Getting Started with DAQmx

Learn 10 Functions in NI-DAQmx and Handle 80 Percent of Your Data Acquisition Applications