Siemens Simatic S7-300 User manual

Getting Started - Commissioning a CPU
31xC: Closed- 
loop control
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SIMATIC
S7-300
Getting Started - Commissioning a CPU 31xC:
Closed-loop control
Getting Started
08/2011
A5E00105534-03
Introduction
1
Preparation
2
Learning units
3
Further Information
4

Legal information
Legal information
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NOTICE
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A5E00105534-03
Ⓟ 09/2011
Copyright © Siemens AG 2011.
Technical data subject to change

Getting Started - Commissioning a CPU 31xC: Closed-loop control
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Table of contents
1 Introduction................................................................................................................................................ 5
2 Preparation................................................................................................................................................ 7
3 Learning units .......................................................................................................................................... 11
3.1 1. Step: Installing the sample project...........................................................................................11
3.2 2. Step: Linking to the user program............................................................................................12
3.3 3. Step: Setting parameters .........................................................................................................13
3.4 4. Step: Trial run ..........................................................................................................................13
4 Further Information .................................................................................................................................. 15

Table of contents
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Introduction 1
Contents of this Getting Started Manual
The practical sample in this Getting Started manual takes you through four steps, showing
you how to commission a fully functional application. You are going to learn how to
determine and configure application-dependent data and how to operate a control circuit.
This process will take one to two hours, depending on your experience.

Introduction
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Preparation 2
Scope
These instructions apply to the following CPUs:
CPU SIMATIC Micro Memory Card
required for operation?
As of firmware
version
313C Yes V3.3
313C-2 PtP yes V3.3
313C-2 DP yes V3.3
314C-2 PtP yes V3.3
314C-2 DP yes V3.3
314C-2 PN/DP yes V3.3
The order number can be found in the manuals, e.g. the operating instructions CPU 31xC
and CPU 31x: Installation (http://support.automation.siemens.com/WW/view/en/13008499).

Preparation
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Requirements
● You have an S7-300 station consisting of a power supply module and a CPU 313C or
314C.
● STEP 7 as of V5.5 is correctly installed on your PG.
The table below shows the STEP 7 version you need for each CPU.
CPU STEP 7 version
313C STEP 7 as of V5.5 + SP1 or STEP 7 as of V5.3 + SP2 with HSP 203
313C-2 PtP STEP 7 as of V5.5 + SP1 or STEP 7 as of V5.3 + SP2 with HSP 204
313C-2 DP STEP 7 as of V5.5 + SP1 or STEP 7 as of V5.3 + SP2 with HSP 203
314C-2 PtP STEP 7 as of V5.5 + SP1 or STEP 7 as of V5.3 + SP2 with HSP 204
314C-2 DP STEP 7 as of V5.5 + SP1 or STEP 7 as of V5.3 + SP2 with HSP 203
314C-2 PN/DP STEP 7 as of V5.5 with HSP 191
● You have downloaded the sample projects from the Internet or have the CD of sample
projects included with the Technological Functions operating instructions.
● You have set up a project for the S7-300 station.
● The PG is connected to the CPU.
● The CPU is correctly connected to a power supply.
● I/O wiring is not required for this sample.
WARNING
Operation of an S7-300 as part of plants or systems is subject to special rules and
regulations, which depend on its field of application. Please make sure that you adhere
to the applicable safety and accident prevention regulations, for example IEC 204
(emergency stop systems).
You risk severe injury, or damage to machines and equipment if you ignore these
regulations.
Ensure the S7-300 is completely disconnected before wiring!
You can come into contact with live wires if the PS 307 power supply module is turned
on or the PS power supply cable is connected to the main power supply.

Preparation
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Layout of the example
2 3
7 6 5 4
1
① Power supply ON/OFF
② Mode selector
③ Mounting rail
④ Programming device with STEP 7 software
⑤ PG cable
⑥ Connecting cable
⑦ Clamp for strain relief
Figure 2-1 Overview of sample layout

Preparation
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Learning units 3
3.1 1. Step: Installing the sample project
Introduction
When installing the sample project, you have the following options:
Installing from CD
1. Take the CD out of the Technological Functions operating instructions.
2. Start the installation program on the CD by double-clicking on the SETUP.EXE file in the
SETUP folder.
The installation program is started.
3. Now follow the instructions in the installation program.
Installing from the Internet
1. Open the directory with the sample projects.
2. Start the installation program by double-clicking the SETUP.EXE file.
The installation program is started.
3. Now follow the instructions in the installation program.

Learning units
3.2 2. Step: Linking to the user program
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3.2 2. Step: Linking to the user program
Procedure
1. Open the project "ZDt26_04_TF_____31xC_PID" in the catalog ...
\Siemens\STEP7\Examples via "File > Open ... > Sample projects" in SIMATIC Manager.
A window, divided into two sections, opens showing the title of the project.
2. Double-click the S7 program "Controlling 2 CONT_C".
The "Sources", "Blocks" and "Symbols" folders are displayed in the right-hand window.
3. Double-click on the "Blocks" container.
All blocks of the S7 program are displayed.
4. With the exception of system data, copy all the blocks to your project under "SIMATIC
300 Station > CPU 3xx > S7 Program > Blocks".
Block Name (in the toolbar) Description
OB 100 RESTART Restart OB
OB 35 CYC_INT5 Time-controlled OB 100 ms
SFB 41 CONT_C Continuous-action PID controller
FB 100 PROC_C Control circuit for continuous controller
DB 100 DI_PROC_C Instance DB for PROC_C
DB 101 DI_CONT_C Instance DB for CONT_C
VAT1 VAT1 Variable table

Learning units
3.3 3. Step: Setting parameters
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3.3 3. Step: Setting parameters
Procedure
1. Start the parameter assignment interface with SIMATIC/STEP7/PID Control Parameter
Assignment.
The input dialog "PID Control" is displayed.
2. In PID control, open your project with "File > Open". Select instance DB 101 for SFB 41.
Acknowledge the dialog with "OK".
You are returned to the parameter assignment screen form. The configured parameters
are displayed. Changes to this sample program are not required.
3. Close the parameter assignment screen form with "File > Close".
The parameter assignment screen form is closed.
4. In SIMATIC Manager, select "SIMATIC 300 Station > CPU 3xx > S7 Program > Blocks".
All blocks of the S7 program are displayed.
5. Download all of the S7 blocks it contains to your CPU via "PLC > Download" (CPU in
STOP mode).
The program and configuration are downloaded from the PG to the CPU.
3.4 4. Step: Trial run
Procedure
1. In the "Blocks" directory, double-click on the variable table "VAT1" in your project.
The variable table for monitoring and modifying is displayed.
2. Go online with "PLC > Connect to > Configured CPU".
At the bottom right, you will see that the CPU is set to "STOP" mode.
3. Activate monitoring with "Variable > Monitor".
The current values of the addresses are displayed in the "Status Value" column.
4. Switch the CPU to RUN.
At the bottom right, you will see that the CPU is set to "RUN" mode. The controller is
started.
5. Modify the setpoint "SP_INT".
You can monitor the output value "OUTV" that is proportional to the setpoint "SP_INT".
6. Call the STEP 7 tool PID Control (see step 3). Select instance DB 101 and click "Online"
mode. In the "Test" menu, select and start the "Curve plotter" function.
You can view the graphic profile of some of the control variables (actual value, setpoint,
control offset, etc.).

Learning units
3.4 4. Step: Trial run
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Further Information 4
Diagnostics/Correction of Errors
Incorrect operator input or inconsistent configuration data may lead to errors.
For information on how to analyze such errors and messages, refer to the S7-300
documentation.
Example:
The "ZEn26_04_TF_____31xC_PID" project contains further samples you can use for
orientation. You can customize all samples according to your personal applications.

Further Information
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