Hi
I have a CompactRIO counter module. I am using it to make period measurument. I am also using a third-party hardware that sends me RPM. The same sensor is connected to either CompactRIO or the third-part hardware.
I know that the resolution of CompactRIO module is bigger than the other device. But when I look at the measurument results, I see that at low frequencies there is big measurument difference in between the two devices.(for example -+500 RPM) When the speed of engine increases, the difference decreases (for example -+200 RPM)
That should not be, there is something wrong. But I could not figure out.
Note: Input filter of CompactRIO counter is set to 1 ns. (I did not try the other options except 1 ns)
Any idea??