Scale Error Before PID Loop?


Thread Starter


Do I need to scale the error value before PID control algorithm? Error will range from -4095 to +4095. Manipulation output will range from 0-1800.

I'm familiar with control theory and tuning principles. However, now I'm designing a control system myself and can't figure out what value ranges to use for inputting into the controller equation Gc.

So I'm using 2 ADC's to measure the Reference and Feedback. Those each give me a value of 0-4095. This is a range of -4095 to +4095.

Ultimately I am trying to control the phase firing angle of a SCR with 0.1 degree precision (I divide up the 180 degrees for each half phase into 1800 pieces).

My question is do I need to scale that value somehow before applying the gains Kp, Ki, Kd for the PID loop?

Should I divide Error by 2.275 (4095/1800) so that my error is scaled to the range of my output?

Thank you