Siemens Module B3 manual Exercise Example

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Automation and Drives - SCE

Starting Up the Software PID Controller (S)FB41 "CONT_C" with STEP 7

A SIMATIC S7-300 is programmed as a PID controller with the software STEP 7. This provides the user with a uniform configuring tool for central as well as distributed configurations. Here, only the most essential aspects can be pointed out. (Additional information is provided in the STEP7 reference manuals.)

The PID controller is parameterized with a special application included in STEP7 -Assigning parameters to a PID Control- by resetting values there in an instance DB associated with the (S)FB

41.This is done as follows:

4.3Exercise Example

The user has to perform the steps below in order to configure the hardware as well as to generate an

S7 program with the functionality of a PID controller, and then load it to a PLC:

1.Call the SIMATIC Manager

Click on symbol 'SIMATIC Manager’

2.Set up new project ( → File → New)

Click on 'New'

 

 

 

 

 

 

 

 

Preface Fundamentals

Discontinuous Action Controllerr

Controller Block (S)FB41

 

Setting the System Appendix

 

 

 

 

 

 

 

 

 

T I A Training Document

Page 40 of 64

Module

 

 

 

 

 

B3

Issued: 02/2008

 

 

 

Control Engineering with STEP 7

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Contents Module B3 Automation and Drives SCE Table of Contents Automation and Drives SCE To 3 days Module C To 3 days Module D Frequency Converter at Simatic S7Learning Objective PrerequisitesHardware and software required PLCFundamentals of Control Engineering Tasks of Control EngineeringControlled Variable Components of a Control LoopFeedback Variable r Disturbance Variable z Setpoint Value wComparing Element Controlling ElementControlled System ActuatorDead Time Characteristics For Step Function for Examining Controlled SystemsAutomation and Drives SCE Proportional Controlled System with a Time Delay Time constantTu Delay time Tg Transition time Proportional Controlled System with Two Time DelaysControllability of P-Tn systems Proportional Controlled System with n Time Delays Controlled Systems without Inherent Regulation Types of Controllers Two Position Controllers Switch-On Value Manipulated Variable Time HysteresisThree Position Controllers Basic Types of Continuous Controllers Proportional Controllers P-Controller Automation and Drives SCE With Integral Action Controllers I- ControllerPI Controllers Controller LayoutDerivative Action Controllers D-Controller PID ControllersObjectives for Controller Adjustment 450.85 Digital Controllers DAC Preface Fundamentals Structogram YESAssignment List Symbol Address Comment ExercisePossible Solution for the PLC Program NetworkD24/AIFillSetpNorm/Norm.value for level setpoint Network 10 Title Task Definition for PID Standard Controller Function Diagram of the control system with a PID controller Use FB 41 ContcDescription Exercise Example Automation and Drives SCE Automation and Drives SCE Automation and Drives SCE Automation and Drives SCE Automation and Drives SCE Automation and Drives SCE Automation and Drives SCE Automation and Drives SCE SP INT PLC’ Automation and Drives SCE Automation and Drives SCE Automation and Drives SCE Tu-TgApproximation GeneralT g Approximation Setting the PI-Controller according to Ziegler-Nichols For setpoint characteristic MAN Solution of the PLC program Setting the PI controller according to Ziegler-Nichols SetpointDiagram of the controller block AppendixInput Parameters Data Value Range Default Description Type Comrst Bool FalseParameter Data Type Value Range Default Lmnhlm Real Lmnllm Parameter Data Value Range Default Description Type Output Parameters