Siemens Simatic S7-400 User manual

Preface, Contents
Structure of a CPU 41x 1
Memory Concept and
Startup Scenarios 2
Cycle and Reaction Times
of the S7-400 3
Technical Specifications 4
Index
Edition 12/2002
A5E00165965-01
Automation System S7-400
CPU Specifications
Reference Manual
SIMATIC
This manual is part of the documentation
package with the order number
6ES7398-8AA03-8BA0

Index-2 AutomationSystem S7-400
A5E00165965-01
!Danger
indicates that death, severe personal injury or substantial property damage will result if proper precautions
are not taken.
!Warning
indicates that death, severe personal injury or substantial property damage can result if proper
precautions are not taken.
!Caution
indicates that minor personal injury can result if proper precautions are not taken.
Caution
indicates that property damage can result if proper precautions are not taken.
Notice
draws your attention to particularly important information on the product, handling the product, or to a
particular part of the documentation.
Qualified Personnel
Only qualified personnel should be allowed to install and work on this equipment. Qualified persons are
defined as persons who are authorized to commission, to ground and to tag circuits, equipment, and
systems in accordance with established safety practices and standards.
Correct Usage
Note the following:
!Warning
This device and its components may only be used for the applications described in the catalog or the
technical description, and only in connection with devices or components from other manufacturers which
have been approved or recommended by Siemens.
This product can only function correctly and safely if it is transported, stored, set up, and installed
correctly, and operated and maintained as recommended.
Trademarks SIMATIC, SIMATIC HMIand SIMATIC NETare registered trademarks of SIEMENS AG.
Third parties using for their own purposes any other names in this document which refer to trademarks
might infringe upon the rights of the trademark owners.
Safety Guidelines
This manual contains notices intended to ensure personal safety, as well as to protect the products and
connected equipment against damage. These notices are highlighted by the symbols shown below and
graded according to severity by the following texts:
We have checked the contents of this manual for agreement
with the hardware and software described. Since deviations
cannot be precluded entirely, we cannot guarantee full
agreement. However, the data in this manual are reviewed
regularly and any necessary corrections included in
subsequent editions. Suggestions for improvement are
welcomed.
Disclaimof LiabilityCopyright W Siemens AG 2002 All rights reserved
The reproduction, transmission or use of this document or its
contents is not permitted without express written authority.
Offenders will be liable for damages. All rights, including rights
created by patent grant or registration of a utility model or
design,are reserved.
Siemens AG
Bereich Automation and Drives
Geschaeftsgebiet Industrial Automation Systems
Postfach 4848, D- 90327 Nuernberg SiemensAG 2002
Technical data subject to change.
Siemens Aktiengesellschaft A5E000165965-01

iii
Automation System S7-400 CPU Specifications
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Preface
Purpose of the Manual
The manual contains reference information on operator actions, descriptions of
functions and technical specifications of the central processing units, power supply
modules and interface modules of the S7-400.
How to configure, assemble and wire these modules (and other) in an S7-400
system is described in the installation manuals for each system.
Required Basic Knowledge
You will need general knowledge of automation to understand this manual.
Target Group
This manual is aimed at people with the required qualifications to commission,
operate and maintain the products described.
Scope of this Manual
The manual applies to the S7-400 automation system.
Changes Since the Previous Version
This manual describes S7 CPUs with firmware version 3.1.
Certification
The SIMATIC S7-400 product range has the following certificates:
•Underwriters Laboratories, Inc.: UL 508 (Industrial Control Equipment)
•Canadian Standards Association: CSA C22.2 Number 142, tested (Process
Control Equipment)
•Factory Mutual Research: Approval Standard Class Number 3611.
You can find details on the certificates and approvals in section 1.1, Standards and
Certificates, of the “Module Specifications” reference manual.

Preface
iv AutomationSystem S7-400 CPU Specifications
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CE Labeling
The SIMATIC S7-400 product range complies with the requirements and protection
objectives of the following EU directives:
•EC low voltage directive 73/23/EEC
•EC electromagnetic compatibility directive 89/336/EEC
C-Tick Mark
The SIMATIC S7-400 product range complies with the requirements of the
AS/NZS 2064 standard (Australia and New Zealand).
Standards
The SIMATIC S7-400 product range complies with the requirements and criteria of
the IEC 61131-2.
Place of this Documentation in the Information Environment
This manual is part of the documentation package for S7-400, M7-400.
System Documentation Package
S7-400/M7-400 •S7-400, M7-400 Programmable Controller; Hardware and Installation
•S7-400, M7-400 Programmable Controllers; Module Specifications
•Automation System S7-400; CPU Data
•S7-400 Instruction List
Navigating
The manual offers the following access aids to make it easy for you to find specific
information quickly:
•At the start of the manual you will find a complete table of contents and a list of
the diagrams and tables that appear in the manual.
•An overview of the contents of each section is provided in the left column on
each page of each chapter.
•You will find a glossary in the appendix at the end of the manual. The glossary
contains definitions of the main technical terms used in the manual.
•At the end of the manual you will find a comprehensive index which gives you
rapid access to the information you need.

Preface
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AutomationSystem S7-400 CPU Specifications
A5E00165965-01
Note
In order to program and commission an S7-400 you require
STEP 7 V52 as well as the following manuals or manual packages:
Manual/
Manual Package Chapter Overview
Standard Software
for S7 and M7
STEP 7 Basic
Information
•Installing and starting up STEP 7 on a programming device / PC
•Working with STEP 7 with the following contents:
Managing projects and files
Configuring and assigning parameters to the S7-400 configuration
Assigning symbolic names for user programs
Creating and testing a user program in STL/LAD
Creating data blocks
Configuring the communication between two or more CPUs
Loading, storing and deleting user programs in the CPU / programming device
Monitoring and controlling user programs
Monitoring and controlling the CPU
•Guide for efficiently implementing the programming task with the programming
device / PC and STEP 7
•How the CPUs work (for example, memory concept, access to inputs and
outputs, addressing, blocks, data management)
•Description of STEP 7 data management
•Using data types of STEP 7
•Using linear and structured programming
•Using block call instructions
•Using the debug and diagnostic functions of the CPUs in the user program (for
example, error OBs, status word)
STEP 7 Reference
Information
Statement List (STL)
for S7-300 and
S7-400
Ladder Logic (LAD)
•Basic procedure for working with STL, LAD, or FBD (for example, structure of
STL, LAD, or FBD, number formats, syntax)
•Description of all instructions in STEP 7 (with program examples)
•Description of the various addressing methods in STEP 7 (with examples)
•Description of all functions integrated in the CPUs
•Description of the internal registers in the CPU
for S7-300 and
S7-400
Function Block
Diagram (FBD) for
S7-300 and S7-400
System and
Standard Functions
Description of the internal registers in the CPU
•Description of all system functions integrated in the CPUs
•Description of all organization blocks integrated in the CPUs
Manual
PG 7xx
•Description of the programming device hardware
•Connecting a programming device to various devices
•Starting up a programming device

Preface
vi AutomationSystem S7-400 CPU Specifications
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Recycling and Disposal
The S7-400 is low in contaminants and can therefore be recycled. To recycle and
dispose of your old device in an environment-friendly manner, please contact a
disposal company certified for disposal of electronic waste.
Further Support
If you have any technical questions, please get in touch with your Siemens
representative or agent responsible.
http://www.siemens.com/automation/partner
Training Centers
We offer a number of courses to help you become familiar with the SIMATIC S7
programmable logic controller. Please contact your regional training center or our
central training center in D 90327 Nuremberg, Germany for details:
Phone: [phone].
Internet: http://www.sitrain.com

Preface
vii
AutomationSystem S7-400 CPU Specifications
A5E00165965-01
A&D Technical Support
Available 24 hours a day, worldwide:
Johnson City
Nuremberg
Bejiing
Technical Support
Worldwide (Nuremberg)
Technical Support
Local time: 0:00 to 24:00 / 365 days
Phone: [phone]
Fax: [phone]
E-Mail: adsupport@
siemens.com
GMT: +1:00
Europe / Africa (Nuremberg)
Authorization
Local time: Mo. - Fr. 8:00 am
to 5:00 pm
Phone: [phone]
Fax: [phone]
E-Mail: adsupport@
siemens.com
GMT: +1:00
United States (Johnson City)
Technical Support and
Authorization
Local time: Mo. - Fr. 8:00 am
to 5:00 pm
Phone: [phone]
Fax: [phone]
E-mail: simatic.hotline@
sea.siemens.com
GMT: –5:00
Asia / Australia (Bejiing)
Technical Support and
Authorization
Local time: Mo. - Fr. 8:00 am
to 5:00 pm
Phone: [phone]
Fax: [phone]
E-mail: adsupport.asia@
siemens.com
GMT: +8:00
The languages of the SIMATIC Hotlines and the authorization hotline are generally German and English.

Preface
viii Automation System S7-400 CPU Specifications
A5E00165965-01
Service & Support in the Internet
In addition to our documentation, we also offer you the benefit of all our knowledge
on the Internet.
http://www.siemens.com/automation/service&support
There you will find:
•A newsletter with all the latest information on your products
•Knowledge Manager to locate the documentation you require
•A forum in which users and specialists throughout the world exchange their
experiences
•Your local contact person for Automation & Drives using our contact database
•Information about our on-site service, repairs, spare parts and much more is
available under the heading “Service”.

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Contents
1 Structure of a CPU 41x 1-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.1 Controls and Indicators of the CPUs 1-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2 Monitoring Functions of the CPU 1-9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.3 Status and Error LEDs 1-11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.4 Mode Selector 1-14. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.5 Design and Function of Memory Cards 1-18. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.6 Multipoint Interface (MPI) 1-22. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.7 PROFIBUS DP Interface 1-23. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.8 Overview of the Parameters for the S7-400 CPUs 1-24. . . . . . . . . . . . . . . . . . .
1.9 Multicomputing 1-26. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.9.1 Peculiarities 1-28. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.9.2 Multicomputing Interrupt 1-29. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.9.3 Configuring and Programming Multicomputing Operation 1-29. . . . . . . . . . . . .
1.10 Modifications to the System During Operation 1-30. . . . . . . . . . . . . . . . . . . . . . .
1.11 CPU 41x as DP Master/DP Slave 1-34. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.11.1 DP Address Areas of the CPUs 41x 1-35. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.11.2 CPU 41x as DP Master 1-36. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.11.3 Isochrone Updating of the Process Image Partition 1-40. . . . . . . . . . . . . . . . . .
1.11.4 Diagnostics of the CPU 41x as DP Master 1-41. . . . . . . . . . . . . . . . . . . . . . . . . .
1.11.5 CPU 41x as DP Slave 1-46. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.11.6 Diagnostics of the CPU 41x as DP Slave 1-51. . . . . . . . . . . . . . . . . . . . . . . . . . .
1.11.7 CPU 41x as DP slave: Station States 1 to 3 1-57. . . . . . . . . . . . . . . . . . . . . . . . .
1.12 Direct Communication 1-64. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.12.1 Principle of Direct Data 1-64. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.12.2 Diagnostics in Direct Communication 1-66. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.13 Consistent Data 1-68. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.13.1 Consistency for Communication Blocks and Functions 1-69. . . . . . . . . . . . . . .
1.13.2 Access to the Working Memory of the CPU 1-69. . . . . . . . . . . . . . . . . . . . . . . . .
1.13.3 Read from and Writing to a DP Standard Slave Consistently 1-69. . . . . . . . . .
1.13.4 Writing Data Consistently to a
DP Standard Slave Using SFC 15 “DPWR_DAT” 1-70. . . . . . . . . . . . . . . . . . . .
1.13.5 Consistent Data Access without the Use of SFC 14 or SFC 15 1-71. . . . . . . .
2 Memory Concept and Startup Scenarios 2-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.1 Overview of the Memory Concept of S7-400 CPUs 2-2. . . . . . . . . . . . . . . . . .
2.2 Overview of the Startup Scenarios for S7-400-CPUs 2-5. . . . . . . . . . . . . . . . .

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3 Cycle and Reaction Times of the S7-400 3-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.1 Cycle Time 3-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.2 Cycle Time Calculation 3-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.3 Different Cycle Times 3-8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.4 Communication Load 3-10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.5 Reaction Time 3-13. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.6 How Cycle and Reaction Times Are Calculated 3-18. . . . . . . . . . . . . . . . . . . . . .
3.7 Examples of Calculating the Cycle Time and Reaction Time 3-19. . . . . . . . . . .
3.8 Interrupt Reaction Time 3-22. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.9 Example of Calculating the Interrupt Reaction Time 3-24. . . . . . . . . . . . . . . . . .
3.10 Reproducibility of Time-Delay and Watchdog Interrupts 3-25. . . . . . . . . . . . . . .
4 Technical Specifications 4-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.1 Technical Specifications of the CPU 412-1;
(6ES7412-1XF03-0AB0) 4-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.2 Technical Specifications of the CPU 412-2;
(6ES7412-2XG00-0AB0) 4-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.3 Technical Specifications of the CPU 414-2;
(6ES7414-2XG03-0AB0) 4-10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.4 Technical Specifications of the CPU 414-3;
(6ES7414-3XJ00-0AB0) 4-14. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.5 Technical Specifications of the CPU 416-2;
(6ES7416-2XK02-0AB0, 6ES7416-2FK02-0AB0) 4-18. . . . . . . . . . . . . . . . . . . .
4.6 Technical Specifications of the CPU 416-3;
(6ES7416-3XL00-0AB0) 4-22. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.7 Technical Specifications of the CPU 417-4;
(6ES7417-4XL00-0AB0) 4-26. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.8 Technical Specifications of the Memory Cards 4-30. . . . . . . . . . . . . . . . . . . . . . .
Index Index-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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Figures
1-1 Layout of the Controls and Indicators of the CPU 412-1 1-2. . . . . . . . . . . . . .
1-2 Layout of the Controls and Indicators of the CPU 41x-2 1-3. . . . . . . . . . . . . . .
1-3 Layout of the Controls and Indicators of the CPU 41x-3 1-4. . . . . . . . . . . . . . .
1-4 Layout of the Controls and Indicators of the CPU 417-4 1-5. . . . . . . . . . . . . .
1-5 Positions of the Mode Selector 1-14. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1-6 Structure of the Memory Card 1-18. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1-7 Multicomputing Example 1-27. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1-8 Overview: Architecture enabling modification
of a system during operation 1-30. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1-9 Diagnostics with CPU 41x 1-43. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1-10 Diagnostic Addresses for the DP Master and DP Slave 1-44. . . . . . . . . . . . . . .
1-11 Intermediate Memory in the CPU 41x as DP Slave 1-47. . . . . . . . . . . . . . . . . . .
1-12 Diagnostic Addresses for the DP Master and DP Slave 1-54. . . . . . . . . . . . . . .
1-13 Structure of the Slave Diagnosis 1-56. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1-14 Structure of the Module Diagnosis of the CPU 41x 1-60. . . . . . . . . . . . . . . . . . .
1-15 Structure of the Station Diagnosis 1-61. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1-16 Bytes +4 to +7 for Diagnostic and Process Interrupts 1-62. . . . . . . . . . . . . . . . .
1-17 Direct Communication with CPUs 41x 1-65. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1-18 Diagnostic Address for the Recipient During Direct Communication 1-66. . . .
3-1 Parts and Composition of the Cycle Time 3-3. . . . . . . . . . . . . . . . . . . . . . . . . . .
3-2 Different Cycle Times 3-8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3-3 Minimum Cycle Time 3-9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3-4 Formula: Influence of Communication Load 3-10. . . . . . . . . . . . . . . . . . . . . . . . .
3-5 Breakdown of a Time Slice 3-10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3-6 Dependency of the Cycle Time on the Communication Load 3-12. . . . . . . . . .
3-7 DP Cycle Times on the PROFIBUS-DP Network 3-14. . . . . . . . . . . . . . . . . . . . .
3-8 Shortest Reaction Time 3-15. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3-9 Longest Reaction Time 3-16. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3-10 Calculating the Interrupt Reaction Time 3-22. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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Tables
1-1 LEDs of the CPUs 1-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1-2 Positions of the Mode Selector 1-15. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1-3 Protection Levels of a S7-400 CPU 1-16. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1-4 Types of Memory Cards 1-19. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1-5 CPUs 41x (MPI/DP Interface as PROFIBUS DP) 1-35. . . . . . . . . . . . . . . . . . .
1-6 CPUs 41x (MPI/DP Interface and DP Module as PROFIBUS DP) 1-35. . . . . .
1-7 Meaning of the BUSF LED of the CPU 41x as DP Master 1-41. . . . . . . . . . . . .
1-8 Reading Out the Diagnosis with STEP 7 1-42. . . . . . . . . . . . . . . . . . . . . . . . . . .
1-9 Event Detection of the CPUs 41x as DP Master 1-45. . . . . . . . . . . . . . . . . . . . .
1-10 Configuration Example for the Address Areas
of the Intermediate Memory 1-48. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1-11 Meaning of the BUSF LEDs of the CPU 41x as DP Slave 1-51. . . . . . . . . . . . .
1-12 Reading Out the Diagnostic Data with STEP 5
and STEP 7 in the Master System 1-52. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1-13 Event Detection of the CPUs 41x as DP Slave 1-55. . . . . . . . . . . . . . . . . . . . . .
1-14 Evaluation of RUN-STOP Transitions in the DP Master/DP Slave 1-55. . . . .
1-15 Structure of the Station Status 1 (Byte 0) 1-57. . . . . . . . . . . . . . . . . . . . . . . . . . .
1-16 Structure of Station Status 2 (Byte 1) 1-58. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1-17 Structure of Station Status 3 (Byte 2) 1-58. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1-18 Structure of the Master PROFIBUS Address (Byte 3) 1-58. . . . . . . . . . . . . . . .
1-19 Structure of the Manufacturer ID (Bytes 4, 5) 1-59. . . . . . . . . . . . . . . . . . . . . . . .
1-20 Event Detection of the CPUs 41x as
Recipient During Direct Communication 1-66. . . . . . . . . . . . . . . . . . . . . . . . . . . .
1-21 Evaluation of the Station Failure in the
Sender During Direct Communication 1-67. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2-1 Memory Requirements 2-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3-1 Cyclic Program Scanning 3-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3-2 Factors that Influence the Cycle Time 3-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3-3 Portions of the process image transfer time 3-5. . . . . . . . . . . . . . . . . . . . . . . .
3-4 Portions of the process image transfer time, H CPUs 3-6. . . . . . . . . . . . . . . .
3-5 User program processing time for the CPU 41x-4H 3-7. . . . . . . . . . . . . . . . . .
3-6 Operating system scan time at scan cycle checkpoint 3-7. . . . . . . . . . . . . . . .
3-7 Increase in Cycle Time by Nesting Interrupts 3-7. . . . . . . . . . . . . . . . . . . . . . . .
3-8 Reducing the Reaction Time 3-17. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3-9 Example of Calculating the Reaction Time 3-18. . . . . . . . . . . . . . . . . . . . . . . . . .
3-10 Hardware Interrupt and Diagnostic Interrupt Reaction Times;
Maximum Interrupt Reaction Time Without Communication 3-22. . . . . . . . . . .
3-11 Reproducibility of Time-Delay and Watchdog Interrupts of the CPUs. 3-25. .

1-1
Automation System S7-400 CPU Specifications
A5E00165965-01
Structure of a CPU 41x
Chapter Overview
In Section You Will Find On Page
1.1 Controls and Indicators of the CPUs 1-2
1.2 Monitoring Functions of the CPU 1-9
1.3 Status and Error LEDs 1-11
1.4 Mode selector 1-14
1.5 Design and Function of Memory Cards 1-18
1.6 Multipoint Interface (MPI) 1-22
1.7 PROFIBUS DP interface 1-23
1.8 Overview of the Parameters for the S7-400 CPUs 1-24
1.9 Multicomputing 1-26
1.10 Modifications to the System During Operation 1-30
1.11 CPU 41x as DP Master/DP Slave 1-34
1.12 Direct Communication 1-64
1.13 Consistent data 1-68
1

Structure of a CPU 41x
1-2 AutomationSystem S7-400 CPU Specifications
A5E00165965-01
1.1 Controls and Indicators of the CPUs
Controls and Indicators of the CPU 412-1
Mode selector
Slot for the memory card
Incoming supply of external backup voltage
Under cover
LEDs INTF, EXTF, BUS1F,
FRCE, RUN, STOP
MPI/PROFIBUS DP interface
BUS1F
CPU 412-1
6ES7412-1XF03-0AB0
Module designation, version, abbre-
viated order number and firmware
version
V3.0.0
Figure 1-1 Layout of the Controls and Indicators of the CPU 412-1

Structure of a CPU 41x
1-3
AutomationSystem S7-400 CPU Specifications
A5E00165965-01
Controls and Indicators of the CPU 41x-2
Mode selector
Slot for the memory card
Incoming supply of
Under cover
LEDs INTF, EXTF, BUS1F,
BUS2F, FRCE, RUN, STOP
MPI/PROFIBUS DP interface
PROFIBUS DP interface
BUS1F
BUS2F
CPU 414-2
6ES7414-2XG03-0AB0
Module designation, version, abbre-
viated order number and firmware
version
V3.0.0
external backup voltage
Figure 1-2 Layout of the Controls and Indicators of the CPU 41x-2

Structure of a CPU 41x
1-4 AutomationSystem S7-400 CPU Specifications
A5E00165965-01
Controls and Indicators of the CPU 41x-3
Mode selector
Slot for the memory card
Under cover
Under cover
Module slot for in-
terface module
LEDs INTF, EXTF, BUS1F,
BUS2F, FRCE, RUN, STOP
MPI/PROFIBUS DP interface
PROFIBUS DP interface
LEDs
IFM1F
BUS1F
BUS2F
IFM1F
CPU 416-3
6ES7416-3XL00-0AB0
Module designation, version, abbre-
viated order number and firmware
version
V3.0.0
Incoming supply of
external backup voltage
Figure 1-3 Layout of the Controls and Indicators of the CPU 41x-3

Structure of a CPU 41x
1-5
AutomationSystem S7-400 CPU Specifications
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Controls and Indicators of the CPU 417-4
Mode selector
Slot for the memory card
Under cover
Under cover
Module slot for in-
terface module 1
Module slot for in-
terface module 2
LEDs INTF, EXTF, BUS1F,
BUS2F, FRCE, RUN, STOP
MPI/PROFIBUS DP interface
PROFIBUS DP interface
LEDs
IFM1F, IFM2F
BUS1F
BUS2F
IFM1F
IFM2F
Under the metal lid
on the left-hand side
Interface for memory expansion
Module designation, version, abbre-
viated order number and firmware
version
V3.0.0
Incoming supply of
external backup voltage
Figure 1-4 Layout of the Controls and Indicators of the CPU 417-4
LEDs
Table 1-1 gives you an overview of the LEDs on the individual CPUs.
Section 1.2 describes the states and errors indicated by these LEDs.

Structure of a CPU 41x
1-6 AutomationSystem S7-400 CPU Specifications
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Table 1-1 LEDs of the CPUs
LED Color Meaning In CPU
412-1 412-2
414-2
416-2
414-3
416-3 417-4
INTF red Internal fault x x x x
EXTF red External fault x x x x
FRCE yellow Active force request x x x x
RUN green RUN mode x x x x
STOP yellow STOP mode x x x x
BUS1F red Bus fault at MPI/PROFIBUS DP
interface 1 x x x x
BUS2F red Bus fault at PROFIBUS DP
interface 2 – x x x
IFM1F red Error at interface submodule 1 – – x x
IFM2F red Error at interface submodule 2 – – – x
Mode Selector
You can use the mode selector to select the current operating mode of the CPU.
The mode selector is a key switch with four switching positions. You can use
different protection levels and limit any program changes or startup options (STOP
to RUN transition) to a certain group of people.
Section 1.4 describes the functions of the mode selector and the protection levels
of the CPUs.
Slot for Memory Cards
You can insert a memory card in this slot.
There are two types of memory card:
•RAM cards
You can expand the load memory of a CPU with the RAM card.
•FLASH cards
You can use the FLASH card to store your user program and your data so that
they are failproof (even without a backup battery). You can either program the
FLASH card on the programming device or in the CPU. The FLASH card also
expands the load memory of the CPU.
You can find a detailed description of the memory cards in Chapter 1.5.

Structure of a CPU 41x
1-7
AutomationSystem S7-400 CPU Specifications
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Slot for Interface Modules
You can insert one interface module (IF module) for each CPUs 41x-3 and 41x-4 in
this slot.
Interface for Memory Expansion
CPU 417-4 also features interfaces for memory expansion. These make it possible
to expand the working memory. (See “S7-400, M7-400 Programmable Controllers,
Hardware and Installation”)
MPI/DP interface
You can connect the following devices to the MPI of the CPU, for example:
•Programming devices
•Operation and monitoring devices
•Additional S7-400 or S7-300 controllers (see Section 1.6).
Use the bus connector with an angular outgoing cable (see the Installation manual,
Chapter 7)
You can also configure the MPI interface as a DP master and use it as a
PROFIBUS DP interface with up to 32 DP slaves.
PROFIBUS DP interface
You can connect the distributed I/O, programming devices/OPs and additional
DP master stations to the PROFIBUS DP interface.

Structure of a CPU 41x
1-8 AutomationSystem S7-400 CPU Specifications
A5E00165965-01
Incoming Supply of External Backup Voltage at the “EXT.-BATT.” Socket
You can use one or two backup batteries –depending on the module type –in the
power supply modules of the S7-400 to do the following:
•Provide backup power for the user program you have stored in RAM.
•Maintain memory bits, times, counts and system data as well as data in variable
data blocks.
•Provide backup power for the internal clock.
You can achieve the same backup power by connecting a voltage between 5 V and
15 V DC to the “EXT.-BATT.” socket of the CPU.
The “EXT.-BATT.” input has the following features:
•Reverse polarity protection
•A short-circuit current limit of 20 mA
You need a cable with a 2.5 mm ∅jack to connect power to the “EXT.-BATT”
socket, as shown in the following illustration. Note the polarity of the jack.
Positive pole Negative pole
2.5 mm jack ∅
Note
You will require the external incoming supply at the “EXT.-BATT.” socket if you
replace a power supply module and want to provide a backup supply for the user
program stored in RAM and the data mentioned above while the module is being
replaced.