PI Terms PI is used to control the response of any closed loop system. It is used specifically in system applications involving the control of drives to provide zero steady state error between Setpoint and Feedback, together with good transient performance.

Proportional Gain (P501)

This is used to adjust the basic response of the closed loop control system. The PI error is multiplied by the Proportional Gain to produce an output.

Integral (P502)

The Integral term is used to reduce steady state error between the setpoint and feedback values of the PI. If the integral is set to zero, then there will always be a steady state error.

+ Error

Setpoint

(AIN1)

Feedback (AIN2)

PGain

I Gain

dt

+

+

 

Output

SFunctions as P, PI controller

SSingle symmetric limit on output

A Method for Setting–up the PI Gains

Underdamped (oscillatory)Critically Damped

OUTPUT

Overdamped

SETPOINT

4–12 Start–Up and Operation

MN735

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Baldor MN735 manual Proportional Gain P501, Integral P502, Method for Setting-up the PI Gains