PI Controller

Hi,

Most electronic controllers have outputs of 4-20mA, but they are not limited to that type of output signal.

Thank you

thanks dear.

If I have sucion pressure controller set value is 20 bar & actual measured value is say 19 bar, in that case what is the output of controller?

If this out put is fed to High signal selector(HSS) which has another input from discharge pressure controller whose set point is 185 bar & actual measured value is 180 bar the what would be the output of HSS.

also request you to pl give me detailed address for site for understanding DCS functioning .

Thanks

It will be an increasing signal the value of which is determined by the P and I settings.

The output of the controller will depend upon make and model. It could be a 3 to 15 psi, voltage, or current output. It will also depend upon how it is set up, ie. what the output is scaled to represent (example: the output is the percentage that equals the amount that a valve is to open).

In order to answer the question accurately, one needs to know the type of controller (i.e. pneumatic or electronic) and how the output is scaled. The output of the controller is not controlled by the type of input signal, but what the controllers output is setup to be.

I hope this helps.

Thanks a lot , very coorect & satsfying answer.

I ahve anohther doubt what is the difference between Low signal selector & high signal selector? as I see function wise both operate in the same fashion.

Also request you to pl get me your details where are in India or overseas? I need more info on DCS pl guide me giving the website details or books details.