How do I measure a frequency of 0 and not cause a error?

[SGofAPG]

Im measuring the frequency of a turbine flow meter to get the flow rate. Occasionally the flow rate is 0. However when using the data assistant, if a 0Hz signal is in effect then the software crashes. Basically Times Out set time then gives an error that no signal was recieved. How can I either measure from 0Hz as a minimum value, or just not have the 'not recieved signal' error. 

[johnsold]

First of all how do you define a zero frequency? Frequency is defined as the number of cycles per unit time. Does your turbine produce digital pulses or an continuous signal?

If it is pulses, set up to count events, not frequency or period. Generate a suitable gate pulse and calculate the frequency from number of events counted/duration of gate pulse. This will work without timeout issues and will produce a zero frequency without problems. If the signal is sinusoidal, the same concept would work, but you need to do some signal processing to define the edges of the cycles you want to count.

Lynn

[SGofAPG]

I figured as much that Id need to do a pulse counting calculate myself. It is a pulse per revolution and I have the calibrated equation to get the data into GPM. I was just hoping there was a more automatic way of getting the frequency.