cRIO9215 for digital tachometer signal?

[GoodManBing]

Hi, may i know if it is possible to for the cRIO9215, which an analog input module for compactrio to read in a digital signal from a tachometer?

Thanks Thanks!!

[Otis]

Hi,

You shouldn't have any problem reading a digital signal with the cRIO-9215.  Just keep in mind that you are reading a digital signal with an analog line, so you will need to do some sort of logic on the analog signal to determine if it's a true or a false.  As long as you don't exceed rates of about 10kS/s on your tach, then you shouldn't have a problem reading the signal.

Another thing to keep in mind is that according the Operators Manual the cRIO-9215 can only handle +/- 30V.  Since some tachs may output signals greater than that, you  may want to optically isolate the tach from the cRIO device.

As long as your signal is within a readable range (+/- 10V) there is no real different between an analog signal and a digital signal as far as the analog to digital converter is concerned.

Regards,

[GoodManBing]

Message Edited by GoodManBing on 10-21-2005 11:14 AM

[GoodManBing]

Thank you, i am currently using the cRio 9215 to implement a position control of a motor by counting the number of rising edges from the tach signal,  the info you provide will be helpful! :smileyhappy