I'm a student doing a project on PID control. I do not know how to use the PID output values to relate to the voltages so that the position of a valve can be controlled. For example, should I just use the PID output value as the ouput
voltage value and supply it to the valve? Thank you for your help.

 

Depending on your type of programming, IEC or ladder, scale your PID CV value to the same range as your PV input PV value.

Typically in ladder logic, field device with 12 bit resolution will have a decimal value of 0 -4095. The output range of your PID block would then be 0 - 4095. The analogue output module of your PLC will interpret this to mean 0 - 100% output (0-5Vdc)

If IEC programming is used, simply scale the PV value and CV value to 0 - 100% and the analogue output module will react accordingly.

Feel free to contact me with regards to any other PID questions.

 

hello

i am a student from india. i have to make a autotuning digital pid controller using ADC, DAC and 8051 microcontroller. Can u please help me....i am using MAX532 DAC and MAX162 ADC . i want to interface it with 8051 as well as make algorithm software in assembly language of 8051 or C prog to run it.....please help me ...
thanking u.
Saheel Shah