I am a beginner for using PLC, and we are going to design a PID control loop to control power source according to the temperature. Is there any example we can share together?

 

I don't know if this helps you?
http://www.omega.com/prodinfo/temperaturecontrollers.html

 

hi,

this might be a little away from where you are because i have little to go on. as i can conclude from what i have seen with plcs, writing code to run pid control is or can be kept simple. but if you were monitoring more than two and up to say twenty temperature inputs there are many ways, chartless recorders to graph and set trends. analogue input and out blocks are common with such recorders. so too are io block set. points are or can be a written word to a numeric register or bit. logic inserted as a control point (worm graphs) are common as temperature is a slow correcting process. Where QA is not accountable
to production or the control is more about monitoring and safeguarding a series of machines. the end use will dictate how responsive the process is and how in depth in code needs to be.

Now first question: will there be a need to use individual temp controllers where individual pid values would or might need to be re-calibrated to allow for the changing of or the replacement of a temp probe, or is the temp actuator a thermostat or a varister? each having its own strong points for use, the action time before critical
temperatures are reached. why the need to control temp? what will if temp control fails? All this and more will have to be answered before control or the code for control is attempted. good luck and remember if you fail to plan you are actually planning to fail.