9401 counter questions

I'm trying to measure rpm of the motor shaft with a proximity sensor and a cDAQ-9174 with NI 9401 module in slot 4.  The exit of the proximity sensor passes from 0V to approximately 4.25V.  The frequency of measurement should be close to 1 Hz to 500 Hz, I hung the signal to pin 16 and the COM to pin 1.  When I select ctr0, the measured value changes radically, as shown in the chart attachd counter image.  I checked my signal clinging to a NI 9205 module and using an oscilloscope VI, as shown in the picture as an attachment.  It shows exactly what I was waiting for the frequency and amplitude.  What could be the problem when you try to use the meter?  I have also tried in MAX and get the same strange results.

Thank you


Have you tried to use one of the examples? Specifically, could you try material input and output-> DAQmx-> entrance of counter-> meter - reading and frequency (On Demand) .vi pulse width.

Tags: NI Hardware

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