We have several PID loops in our process and I have been wanted to install a deadband so that minor changes to the incoming process variable are ignored in the PID2 control block.

We have set up several of these PID2 blocks but we have only learned of these by trial and error. We have no education or literature to refer to in regards to programming the PID2 blocks. So any information on how to smooth the control of these is greatly appreciated. All of our PID blocks have only one process variable coming in controlling one process item out. What we have now is in one case a tank level being controlled by a variable position valve. Any movement, wave or fluctuation of level causes the valve to start moving but we want to ignore lets say a three to five percent change in the incoming variable. Any suggestions?

 

Could you please tell us what is the machine in question - a PLC for example, and which manufacturer, model and programming software?

Meir

 

Meir
I want to construct a PID controller with feedback, for a small motor control . Could you describe to me, the schematic analog circuit (comparator,integral,differential,proportional,adder and inverter, with the right resistors, capacitors, operation amplifiers (for example with LM741 op-amp, or other). Thank you very much!

 

No, maybe you didn't understand me. I want to construct a simple analog PID for some homework to my University.

I don't know some specific PID. I have some knowledge for the construction and mathematical model, but I haven't oscilloscope and other essential instruments for help. Could you like to send me, any analog PID schematic diagram with feedback? A simple educator, with 10-15 voltage supply! Or another if you want? Thank you!

 

Costas

In the good old days (35 years ago) I used to read the Burr-Brown Opamp handbook.

Try Analog Devices applications notes - for example.

Meir