Re: To PID or not to PID

"Francis" <newreader@xxxxxxxxxxxxxxxxxxxxxxxxxxxxx> wrote in message
news:qnFwe.12375$Ar5.10097@xxxxxxxxxxxxxxxxxxxxxxx
> Did you answer the questions I raised?
> Probably only "cbolwerk" who started the thread can do that.
> If what I suggested (that the PD pump speed sets the flow) is right, then
> you have no better way of measuring the flow. The PD pump speed is
probably
> as good a measurement of the flow as you will get. (It would be far more
> accurate short term than weight changes)
> That is not "Don't bother so find our which way you're _actually_
headed."
> What did you mean by NNExE? (Tried googling it too)
> Was your comment slightly offensive ?

Francis,

"NNExE" = North North East by East.

It seems Jerry was making a smart remark about your method to indirectly
measure the flow using pump speed.

You stated: "Just set the speed, possibly modifying for the density if that
can vary". Although the OP didn't state what product he was dealing with,
with all but a few, it isn't all that easy to accurately measure _density_
on the fly - a weight measurement will be required somewhere to get mass
flow.

HTH,
Cameron:-)


.

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