05-17-2018 07:37 AM
Hi ALL,
I am trying to read flow from Flow Meter (specification attached). K-factor = 24 Imp/l. = 0.0417 l/imp. So, I count edges inside the loop (time = 1000 ms) then multiply by 60 then multiply by 0.0417= l/min.
I have also attached modified example VI for my needs.
I don't know why I am reading flow 50 l higher then I am having on digital flow indicator.
Did anyone have the same issue?
Thanks,
gregorian7
05-17-2018 07:50 AM - edited 05-17-2018 07:51 AM
Hi gregorian,
I also use several KEM flowmeters, mostly the smaller ones…
And I read the flow basically the same way: reading a counter, getting the difference to previous value and scale by K factor.
I only recommend to do some averaging: with your current VI you will only get values with a step of 60*0.0417 l/min…
I don't know why I am reading flow 50 l higher then I am having on digital flow indicator.
Well, when your VI runs fine (and IMHO it does) then this digital flow indicator might be configured wrong…
Did you set it's display range from 50 to 1000l/min as stated in your datasheet? Don't do this: the measurement range still is 0…1000l/min! (Zero pulses from flowmeter indicates zero flow instead of 50l/min flow)
05-17-2018 10:44 AM
Thanks for you reply GerdW.
ZHM 07 KR.
I think, I am doing something. I am getting wrong readings. I've connected flow turbine in the circuit and read the same value that on the digital indicator.
I think my wires are fine. Ub+ to +15V PSU, SIngnal to counter and 0V to 0 on PSU.
Maybe I should read frequency rather then impulses.
Regards,
gregeorian7
05-21-2018 07:39 AM
Hi GerdW,
Could you give a clue how can I averaging the reading. As I read signal from 4 pressure transducers in the same loop and plot them in XY Graph, the graph is not readable as flow is fluctuating a lot.
Many thanks,
Gregorian7