Dear Prahlad / Kashyap,

I am sorry you will be disappointed in your serach for a good and PRACTICAL article on PID loops instaed of what you already get to read in the standard academic books. I have visited numerous sites that claim to give away PID alogorithms - but there always is a payment of some kind involved.

It generally transpires that PID algorithms fall into the category of Intellectual Property and nobody is willing ( and maybe should not ?) to give it away free.

And please note except in a generalized area like temperature control, there is no universal PID solution for all concievable setups. the variations are too many.

Designing the PID loop is one thing but evolving the right tune up sequences is an altogether different ball game.

This is one area where it hepls a lot to get your fundamentals very strong.

Am I sounding like a moron ?!

Here are some links:

http://www.expertune.com/tutor.html

And I have a good simulator which I had downloaded some time back. Called Process Control Simulator V1.051 from Hot Pepper Software. Try Googling for it. If you fail to loacte it I can mail it to you ( 1.3Mb)

Bye

Raghu