ROBOTC PID CONTROL MANUAL

This prevents the contro ller from over -reacting to mi nor chan PID calculations CNT -APG002-EN 5 Р’В® Figure 5: Integral output adde d to propor tional output The value of the inte gral calculation can build up o ver time (becau se it is the sum of all past errors), and this built -up value must b e overcome before the system can change direction. The longer the mea sured variable is no t at set- poin t, the l arger the out put of th e integra l cal Р’В® Chapter 1 O v erview of PI D control 4 CNT -A PG002-EN Figure 4: The ef fects of propor tional bias on system output Integr al calculation The int egral calculatio n responds t o the leng th of time the measured vari- able is not at setpo int. Thes e calculations are indep endent of ea ch other but are combi ned to determine the response of the controller to the error. PID calculations CNT -APG002-EN 3 Р’В® PID calculatio ns A PID loop pe rforms three calculati ons: the proportion al ca lculatio n, the integral ca lculation, and the derivative calcu lation. The si gma ( РћР€ ) symb ol indica tes that a sum is being perfor med. Figure 2 i llustrat es how a typi cal PID l oop works. Р’В® Chapter 1 O v erview of PI D control 2 CNT -A PG002-EN Ho w PID loops w or k A PID l oop p erfo rms pr opor tio nal, inte gra l, an d deri vati ve cal cul ati ons to calculat e syst em output.

This chapter provides an overview o f PID control. Thes e con- trollers in c lude the Tracer MP580 /581, AH540/541, and MP501 controllers. 32 Cascade control- firsР”В¬NT -APG002-EN 1 Р’В® Chapt er 1 Ov erview of PID contr ol This guide will hel p you set up, tune, and troubleshoo t proportional, inte- gral, derivative (PID) control loops used in Tracer controllers. Р’В® Conte nts iv CNT -A PG002-EN C ha p t e r 4 A pplicat ions. Sinc e The Trane Company has a policy of cont inu- ous produc t improve ment, it reserves the Р”В¬NT -APG002-EN iii Р’В® Cont ents C h a p t e r 1 Ov er view of PID cont r ol. and shall not be used or reproduc ed in whole o r in part, except as inte nded, without the written perm ission of American Standard Inc.

ROBOTC PID CONTROL MANUAL

PID Control in T racer Controll ers This manual and the information in it are the property of Am erican Standard Inc. Р’В® CNT -APG0 02-EN Applications Guide PID Contr ol in T r acer Contr ollersР”Р„pplications Guide PID Contr ol in T r acer Contr ollers CNT -APG0 02-EN Oct ober 200 1 Р’В®

Robotc pid control