what is cascade loop and how it work and why it used instead of PID single loop

what is cascade loop and how it work and why it used instead
of PID single loop?

In cascade, Which loop is faster and slower?

Please explain with loop drawing and example...

Question Posted / mayur kevadiya

2 Answers
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what is cascade loop and how it work and why it used instead of PID single loop? In cascade, Whi..

Answer / rajesh

in cascade loop
the parameter to be controlled is in series with another
parameter which is to be measured for normal operating
conditions

i.e 2 manipulated variables are in series
it is used in fractional distillation system , boiler
operation in power plants etc

in pid
only one variable is measured and controlled at a time
it is used for temperature , pressure , flow control system

for drawing pls search in google

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what is cascade loop and how it work and why it used instead of PID single loop? In cascade, Whi..

Answer / mithilesh kumar

cascade loop is the combination of two pid control.
where 1st controller output ie mv is the input of 2nd
controller.
1st contrroler more fater than second controoler.
it's used in boiler three element.
it's control feed water flow,drum level and steam flow.
drawing is not possible here.
but i am trying.
controller checked steam flow as well as drum level then it
gived command to control valve as per requirement.

Is This Answer Correct ?

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9 No

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