Answer / nimesh

PID means proportional integral deerivative.
PID used to eliminate offset & for least maximum deviation.
OR
PID means piping & instrumentation.
PID used to eloborate plant layout with all instrumentation.

Answer / murthy

PID- proportional integral and derivative
there different types of controlling techniques,
combinations of these parameters in designing controllers.
it depends on what type of errror occurs in ur
system,deviation from ur set point,time u want ur
controller to take action.
if u want quick acting one then go for only proportional
controller,the disadvantage is you get higher deviation.
if u want to minimze error (measured-set value) go for
integrated controller,disadvantage-your final forms cyclic
fluctuations.
derivative is taken into acount when u want zero cycling
always it is not suggeted to go for PID controller,as it is
costly,ur system may not need it at all.for eg if u want to
control level of a tank with 2 feeds and one withdrawl u
dont need integral action so u can go for PD controller
only

Answer / r sridhar

PID is Proportional Integral and derivative Control.this
closed loop control system is the basis on which a DCS
works.In a Distributed Control system environment you will
find almost all the controllers are of PID type of
Controllers.

Answer / baskar

pid are the controller where it can used in closed loop
system or non-interacting level system.

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