conversion of turbine flow meter


My apologies for the query, but this software is all new to me. I have a cDaq-9188 8 medium chassis containing several modules including 2 off 9401 counter modules, I run signal express version 6.0.0.

My problem is that I have 3 miniature flowmeters turbine (GEMS units FT-110 series) which give various pulse widths depending on what is the 5V square waves.  I brought to the entrance of my 9401 and look of good signals so guess that's my express configuration signal which is the cause of the problem,

I connected the + ve and gnd outputs of the flowmeters Com, DIO1 + Com and DIO3, DIO0 + Com on one of my 9401 cards.

I can see the increment in the number of pulses on measurement & automation Explorer when I run test for this module Panel and watch the chefs of edge that my system can see the pulse from trains.

When configuring the express signal I need it to read in l/min, 58-575Hz corresponds to 0.5 to 5 l/min, but I can't seem to convert the pulse in l/min.

If I select DAQmx acquire > counter entry > frequency it gives me the possibility of updated the custom scale, but every time that I run it I get the error signalling DAQ assistant upward.  I tried many synchronization settings with no luck.  The only time where I have this power as successfully is using counter entry > County of edge, but I'm stuck on how to convert l/min as it has no function of scale (I know!)

Any help appreciated.


I think that he is referring to l/min in litres per minute, and I guess the Freq of flow are the values of this compilation on the scale.
If this is the case; Carl, it seems to me you must configure a custom scale. You can do it in the channel settings tab in the DAQmxAcquire stage. Under custom scale select Create new, and then select map scale. Min/max Freq should match your flow min/max.

I have attached a few screenshots for reference.

Let us know if we are on the right track, otherwise we might need more information; FOR EXAMPLE. file seproj and a bit more info on the flow meter (type of connection, the output signal, etc.).
In addition, a brief look at the documentation on this flow meter recommends the use of a pull-up resistance. Might want to look there as well.

Tags: NI Products

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