flow meter, cpu 1214c,

If you wire the pulse train input as a HSC input, set it to frequency and adjust the integration time values in the hardware configuration to suit.

The result will be an analog signal representing 0 to 100% flow in pulses per second.

You will likely want to normalize and scale this input signal to generate the various user units you need.

For example, to scale from 0-100%,

If I read the specs correctly, NORM function with input range in 0-1150. The output will be floating point from 0.0 to 1.0.

Take the normalized output and feed to a SCALE block.

The min max parameters for the SCALE block will convert the NORM block's output to user units.

Put in 0 for min, and max range value for whatever units are available.

The sensor is not guaranteed to be linear below a certain value.  If you perform a calibration at those lower levels, you can override the norm/scale results and use a look-up table for the low end flow values rather than indicating they are out of range on the HMI.

bruno_cardoso

Hello,

I’m starting to learn how to program a PLC (ladder), as such my knowledge is greatly limited/reduced. So I will appreciate all the help possible.

I’m doing a project where I trigger a micro pump and I would like to measure the flow.

I’m using a CPU 1214C (DC/DC/DC), an SM 1231 (8AI – 13bit) to receive the signal and a KTP700 panel 7’’ to show the value.

To measure the flow rate I’m using an Omega component (FTB2003), which has the following characteristics (http://www.omega.com/manuals/manualpdf/M3236.pdf):

-         -  The output signal is a square wave signal, whose frequency varies linearly with flow rate;

Flow Range		Pulse		Frequency
GPM	LPM	Per Gallons	Per Liters	Output
0.7 - 4	0.25 - 15	17400	4600	76 - 1150 Hz

 

The pump part I can do, however I do not know how to handle the flow sensor signal.

How can I do this? Is there some block that I can use?

 

Can you help me please?

Thanks in advance,

Bruno