Siemens SIMATIC NET CP 243-1 Technical Manual

Preface
Notes on product
Table of contents
List of figures
List of tables

SIMATIC NET

CP 243-1
Communications processor
for Industrial Ethernet

Technical manual

Introduction

Features and functions

Installation and commissioning

Configuration

Programming

Diagnostics

Appendix A: Technical data

Appendix B: Example

Appendix C: Timeout

SIMATIC NET –

Support and training

Copyright Siemens AG, 2002, All rights reserved

Passing this document on to third parties, reproducing this
document or using or relating its contents is not permitted without
express 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
Automaton and Drives
Postfach 48 48

D-90327 Nürnberg

Siemens Aktiengesellschaft J31069-D0428-U001-A1-7618

Liability exclusion

We have checked the contents of this Manual to ensure that they
match the hardware and software described herein. However,
because deviations cannot be completely ruled out, we cannot
guarantee complete conformance. The information contained in this
document is checked regularly and any necessary corrections are
included in subsequent editions. We are thankful for any
recommendations or suggestions.

We reserve the right to make technical changes.

Classification of safety instructions

This manual contains instructions that should be observed to ensure your personal
safety and to protect the equipment from damage. The instructions are highlighted
in the manual by a warning triangle and are marked as follows according to the
level of danger:

Danger

!

!

!

indicates an imminently hazardous situation which, if appropriate precautions are
not taken, will result in death or serious injury.

Warning

indicates an imminently hazardous situation which, if appropriate precautions are
not taken, may result in death or serious injury

Caution

used with a warning triangle indicates an imminently hazardous situation which, if
appropriate precautions are not taken, may result in minor injury.

Caution

used without a warning triangle indicates an imminently hazardous situation which,
if appropriate precautions are not taken, may result in property damage.

Attention

indicates an imminent situation which, if the instructions are not adhered to, may
result in an undesirable result or state.

Note

highlights an important item of information about the product or its use, or indicates
a section of the instructions that deserves careful attention as it contains informa­tion that may be beneficial to the user.

Trademarks

SIMATIC, SIMATIC NET, SINEC and SIMATIC NET Networking for Industry®
are registered trademarks of Siemens AG.

Other designations in this document may be trademarks whose use by third parties
for their own purposes may infringe on the rights of the trademark holder.

Safety-related information on the product

Before using the product described here, it is imperative that you observe the fol­lowing safety-related information.

Qualified personnel

The equipment may be commissioned and operated by qualified personnel only.
For the purposes of the safety instructions in this instruction manual, a Qualified
Person is one who is authorized to commission, ground and label devices, systems
and circuits in accordance with accepted safety standards.

Intended use of hardware products

Please observe the following information regarding the intended use of hardware
products:

Caution

The device may only be used in applications as provided for in the catalog and in the
technical description, and only in connection with non-Siemens products and compo­nents that have either been recommended or approved.

Successful and safe operation of this equipment is dependent on proper transport,
handling, storage, erection and installation, as well as careful operation and mainte­nance.

Before using the supplied sample programs or programs that you created yourself,
ensure that running systems cannot endanger persons or damage machines.

EG regulation: Commissioning is prohibited until it has been established that the ma­chine into which this component is to be installed is in compliance with the regulations
of the 89/392/EWG directive.

09/02 Preface

Preface

Purpose of this manual

This manual is designed to support you in using the CP 243-1 communications
processor. You are provided with information on how to employ this communica­tions processor to communicate via Industrial Ethernet (IE).

Prerequisites

A prerequisite for understanding how the CP 243-1 works is familiarity with this
manual and the "SIMATIC S7-200 Automation System" (MLFB: 6ES7298-8FA21­8AH0) manual. You must also have a basic understanding of the TCP/IP protocol.

Target group

This manual is directed toward engineers, programmers, commissioning engineers
and maintenance technicians with a general knowledge of automation and com­munication systems and human machine interface systems.

Sample program

This manual contains a sample program that provides you with information and as­sistance in programming the CP 243-1. This sample program was created with
STEP 7-Micro/WIN 32 (MLFB: 6ES7 810-2BC02-OYXO) and can be run on an S7­200 CPU, type 224. To run this sample program on another S7-200 CPU, you may
have to adjust the configuration of the program.

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Notes on product

Address label: MAC address
The CP 243-1 is delivered with a fixed MAC address. The MAC address is affixed
to the underside of the top cover of the device.

MLFB number, scope of delivery

Product name MLFB Scope of delivery

CP 243-1 6GK7 243-1EX00-0XE0 CP, documentation on CD-ROM

CP 243-1

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09/02 Table of contents

Table of contents

Preface............................................................................................................... 1

Notes on product.............................................................................................. 2

List of figures.................................................................................................... 5

List of tables ..................................................................................................... 6

1 Introduction .............................................................................................. 7

2 Features and functions............................................................................ 9

2.1 Overview ..............................................................................................................9

2.2 S7 communication via Industrial Ethernet ......................................................... 10

2.2.1 Application.......................................................................................................... 10

2.2.2 Types of communication ....................................................................................11

2.2.3 Communication partners ....................................................................................11

2.3 Security ..............................................................................................................15

2.3.1 Configuration...................................................................................................... 15

2.3.2 Data security ......................................................................................................16

2.3.3 Integrity of communication ................................................................................. 16

2.4 Connections .......................................................................................................17

2.5 Displays: Front LEDs ......................................................................................... 18

3 Installation and commissioning............................................................ 20

3.1 Dimensions for installation in a control panel .................................................... 24

3.2 Dimensions for installation on a DIN rail ............................................................24

3.3 Installation in a control panel ............................................................................. 25

3.4 Installation on a standard DIN rail...................................................................... 26

3.5 Replacement of the CP 243-1............................................................................ 27

3.6 Removing the CP 243-1..................................................................................... 27

4 Configuration.......................................................................................... 28

4.1 Configuration options .........................................................................................28

4.2 Value ranges of the configuration data ..............................................................30

4.2.1 IP address ..........................................................................................................30

4.2.2 Subnet mask ......................................................................................................30

4.2.3 TSAPs ................................................................................................................ 30

4.3 Configuring a CP 243-1 using STEP 7 Micro/WIN 32 .......................................31

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4.4 Configuring a CP 243-1 from a user program.................................................... 36

4.4.1 Occupied system flag area (SM area) ...............................................................37

4.4.2 Structure of the Configuration Data Blocks (CDB)............................................. 38

4.4.3 Structure of the Network Parameter Blocks (NPB) ............................................ 42

4.4.4 Structure of the Network Data Blocks (NDB) ..................................................... 43

4.5 Configuring a communication partner with STEP 7 ...........................................45

4.6 Behavior of CP 243-1 in the event of configuration errors ................................. 49

5 Programming.......................................................................................... 50

5.1 ETHx_CTRL....................................................................................................... 51

5.2 ETHx_CFG......................................................................................................... 53

5.3 ETHx_XFR .........................................................................................................54

6 Diagnostics............................................................................................. 57

6.1 Diagnostics options ............................................................................................ 57

6.2 Error messages of the CP 243-1 ....................................................................... 60

Appendix A Technical data......................................................................... 66

Appendix B Example ................................................................................... 67

Appendix C Timeouts.................................................................................. 73

Abbreviations.................................................................................................. 75

SIMATIC NET – Support and training............................................................ 76

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List of figures

Fig. 1. System overview .....................................................................................................12

Fig. 2. Connections ............................................................................................................ 17

Fig. 3. Front with LED displays .......................................................................................... 18

Fig. 4. Space requirements for installation......................................................................... 23

Fig. 5. Dimensions for installation in a control panel.......................................................... 24

Fig. 6. Dimensions for installation on a DIN rail .................................................................24

Fig. 7. "Properties – S7 connection" mask ......................................................................... 46

Fig. 8. Calling the ETHx_CTRL subroutine ........................................................................ 51

Fig. 9. Calling up the ETHx_CFG subroutine..................................................................... 53

Fig. 10. Calling up the ETHx_XFR subroutine ..................................................................... 55

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List of tables

Table 1: Functions of individual LED displays....................................................................... 19

Table 2: System flag area ..................................................................................................... 37

Table 3: CDB structure .......................................................................................................... 41

Table 4: NPB structure .......................................................................................................... 42

Table 5: NDB structure .......................................................................................................... 44

Table 6: Configuration of read/write commands ...................................................................44

Table 7: Input parameters (ETHx_CTRL) .............................................................................51

Table 8: Return parameters (ETHx_CTRL) ..........................................................................52

Table 9: Input parameters (ETHx_CFG) ............................................................................... 53

Table 10: Return parameters (ETHx_CFG) ............................................................................ 54

Table 11: Input parameters (ETHx_XFR) ............................................................................... 55

Table 12: Return parameters (ETHx_XFR)............................................................................. 56

Table 13: Global errors and their error codes ......................................................................... 58

Table 14: Structure of NPB memory areas ............................................................................. 59

Table 15: Error messages (error byte) ....................................................................................63

Table 16: Error messages (error word) ...................................................................................65

Table 17: Technical data ......................................................................................................... 66

Table 18: Timeouts at the Ethernet......................................................................................... 73

Table 19: Timeouts at the S7 bus ........................................................................................... 74

Table 20: Frequently asked questions .................................................................................... 78

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1 Introduction

Definition and application

The CP 243-1 is a communications processor designed for operation in an S7-200
automation system. It is used for connecting an S7-200 system to Industrial
Ethernet (IE). The CP 243-1 also facilitates communication via Ethernet for the
low-end performance range of the S7 product family. As a result, S7-200 can be
remotely configured, programmed and diagnosed via Ethernet using STEP 7 Mi­cro/WIN 32. Moreover, an S7-200 can communicate with another S7-200, S7-300
or S7-400 controller via Ethernet. It can also communicate with an OPC server.

In the open SIMATIC NET communications system, Industrial Ethernet is the net­work for both the coordination level and the cell level. Technically, the Industrial
Ethernet is an electrical network built on the basis of a shielded coaxial cable,
twisted pair cabling or an optical network using a fiber optic cable. Industrial
Ethernet is defined by the international standard IEEE 802.3.

Continuous communication in the industry sector

Industrial Ethernet is an integral part of the SIMATIC NET concept, which together
with PROFIBUS and the AS Interface ensures continuous networking of the coor­dination, cell and field levels.

Compatibility

The CP 243-1 (6GK7 243-1EX00-0XE0) described here can be used for S7 com­munication. The CP 243-1 can be connected to various types of S7-200 CPUs
(222, 224, 226 and 226XM):

• CPU 222 Rel. 1.10 or higher

• CPU 224 Rel. 1.10 or higher

• CPU 226 Rel. 1.00 or higher

• CPU 226XM Rel. 1.00 or higher

A maximum of 2 extension modules can be mounted on the CPU 222. In contrast,
up to 7 extension modules can be connected to the 224, 226 and 226XM CPUs.

Attention

Only one CP 243-1 should be connected per S7-200 CPU. It cannot be guaranteed
that the S7-200 system will operate properly if additional CP 243-1 are connected.

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The CP 243-1 software is compatible with the following standards:

• S7 XPUT/XGET and S7 READ/WRITE

• S7-200 I/O bus specifications

Planning

The CP 243-1 is configured using STEP 7 Micro/WIN 32, version 3.2.1. or higher.
The CP 243-1 is always delivered with a fixed MAC address. The IP address and
the subnet mask either must be configured or they must be retrieved from a
BOOTP server via the BOOTP protocol. For the purpose of monitoring connections
(Keep Alive), a time can be configured for all TCP transport connections with active
and passive partners. A total of 8 connections to other controllers can be main­tained at any one time.

Programming

To program the communication in the user program, use the "Ethernet Wizard" in
STEP 7 Micro/WIN 32; see Chapters 4 and 5.

Configuration

The CP 243-1 firmware is programmed into the Flash memory during production
and is permanently stored there.
System conditions or dynamic variable contents that are generated during
CP 243-1 operation do not survive a loss of power.
The CP 243-1 is configured with STEP 7 Micro/WIN 32, version 3.2.1 or higher,
and the configuration is stored in the DB of the S7-200 CPU as non-volatile data.
Upon booting, the CP 243-1 reads the configuration out of the CPU and initializes
itself accordingly.

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2 Features and functions

2.1 Overview

The CP 243-1 features the following functions:

• S7 communication

− Performant data communication via Industrial Ethernet. Communication is

based on standard TCP/IP

− Ethernet access via an RJ45 socket

− Simple connection to an S7-200 system via the S7-200 backplane bus

− Facilitates a flexible and distributed automation structure

− Remote programming, configuration and diagnostics of an S7-200 system

(e.g. program upload and download or status displays) via Industrial
Ethernet and STEP 7 Micro/WIN 32.

− Basis for simple further processing and archiving of process data

− Enables simultaneous communication with up to 8 S7 controllers

− Provides a connection to S7-OPC

− Simple network administration

− Modules can be exchanged without requiring repeat program-

ming/configuration (plug & play)

− S7 communication services, "XPUT/XGET", as client and server

− S7 communication services, "READ/WRITE", as server

• Watchdog timer

The CP 243-1 is equipped with a Watchdog circuit. The Watchdog starts each
time CP 243-1 starts up. Typically, the Watchdog monitoring time is 5 s. Due to
component-related tolerances, this time can increase to 7 s. If the Watchdog
monitoring time sets in, a reset of the CP 243-1 is automatically brought about.
This restarts the CP 243-1. During this time, the CP 243-1 reports a "Parity Er­ror" to the S7-200 CPU. Handling of this type of error is described in the STEP 7
Micro/WIN 32 documentation.

• Address assignment via preset MAC address (48 bit value).

The MAC address is assigned to each CP 243-1 at the factory. It is printed on a
label affixed to the underside of the upper enclosure cover.
An IP address can be assigned to the CP 243-1 via the preset MAC address us­ing the BOOTP protocol.

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2.2 S7 communication via Industrial Ethernet

2.2.1 Application

The S7 communication via Industrial Ethernet makes program-controlled commu­nication via communication SFBs/FBs and configured S7 connections possible.
The CP 243-1 supports S7 communication via Industrial Ethernet by means of the
XPUT/XGET and READ/WRITE services. In general, up to 212 bytes of user data
can be transmitted per command. However, if the CP 243-1 is being operated as a
server, up to 222 bytes can be transmitted per read operation.

The CP 243-1 supports up to 8 communication channels to clients or servers on
one or more remote communication partners. The CP 243-1 operates according to
the client/server principle per channel. Per channel, only one command at a time is
received, processed and responded to with a positive or negative response. Only
after a response has been sent will the CP 243-1 accept another command.

If the CP 243-1 receives more than one command on a channel configured as a
server, only the first command is processed and the following commands are ig­nored until the transaction is completed, i.e. until a response has been sent. The
CP 243-1 is not equipped with channel-specific command management and does
not buffer commands.

Prerequisites for communication with a PC/PG

As before, the S7-200 CPU can still be accessed by a PG/PC via the PPI interface.
In addition, it can also be accessed via the CP 243-1 through Ethernet. The follow­ing prerequisites must be met to use this alternative:

− An Ethernet card is inserted in the PG/PC and configured, and there is an
Ethernet or TCP/IP connection to the CP 243-1 (possibly through routers,
firewalls, ...)

− STEP 7 Micro/WIN 32, version 3.2.1 or higher, is installed on the PC/PG.

− The CP 243-1 has been assigned a valid IP address. This address can be

defined in the configuration or retrieved from a BOOTP server via the
BOOTP protocol.

At this time, only one STEP 7 Micro/WIN 32 can communicate with the S7-200
CPU via a CP 243-1.

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2.2.2 Types of communication

The CP 243-1 is provided with three types of communication relationships that can
be applied either individually or in combination.

1. Connection to STEP 7 Micro/WIN 32

2. Connection to further, remote components of the SIMATIC S7 family

3. Connection to OPC-based applications on a PC/PG

2.2.3 Communication partners

• S7-200 CPU with CP 243-1

• S7-300 CPU with CP 343-1 or CP 343-IT

• S7-400 CPU with CP 443-1 or CP 443-IT

• PG/PC with OPC server

• PG/PC with STEP 7 Micro/WIN 32

In the STEP 7 HW-Config program, you can identify which types of S7-300 CPUs
and S7-400 CPUs support the S7 protocol, XPUT/XGET, and, hence, which ones
can communicate with the CP 243-1. When you select an S7-300 or S7-400 CPU
in the catalog window in the program, the selected CPU must support the "S7
communication" function.

For systems in the S7-300 series, XPUT/XGET can only be operated via Ethernet
with a communications processor of version 1.1 or higher. You can identify the
communications processor version by looking at the MLFB number, among other
things. If you use a CP 343-1, the MLFB number must contain the sequence
"EX11“.

The CP 443-1 ISO cannot communicate with the CP 243-1, since the CP 443-1
ISO do not have TCP/IP and RFC 1006 on board.

Attention

Only one CP 243-1 should be connected per S7-200 CPU. It cannot be guaranteed
that the S7-200 system will operate properly if additional CP 243-1 are connected.

Note

When communicating with an OPC server, it should be noted that the CP 243-1
does not support the service that automatically queries which objects are present
in the S7-200 (e.g. DBxx...).

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Overview:

S7-200

PC

BOOTP

max. 8 x

xput / xget read / write

...

CPU 22x

CP 243-1

S7-200 S7-300 S7-400

CPU 22x

CPU 3xx

...

CP 243-1

......

CP 343-1/IT

1 x

PC

Micro/WIN

Ethernet

OPC-Server

CPU 4xx

......

CP 443-1/IT

OPC-Client

PC

Fig. 1. System overview

You can have a CPU 22x with CP 243-1 communicate with other S7-200, S7-300
and S7-400 systems, as well as with an OPC server.
In this case, a maximum of 8 connections are possible in addition to a STEP 7 Mi­cro/WIN connection (see Fig. 1).

Configuring and programming connections for S7 stations

In order to configure the communication between an S7-200 and an S7-300,
S7-400 or OPC server, you will require both STEP 7 Micro/WIN 32, version 3.2.1 or
higher, and STEP 7, version 5.1 or higher, with Service Pack 3 or higher (with NCM
for Industrial Ethernet) (see Chapter 4.5).

STEP 7 Micro/WIN 32 is used for configuring and programming the S7-200 station,
while STEP 7 with NCM for Industrial Ethernet is required for configuring and pro­gramming the S7-300, S7-400 or the OPC server.

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Data exchange via Industrial Ethernet

The exchange of data via the CP 243-1 is based on Ethernet and is therefore not
deterministic, i.e. response times cannot be guaranteed. Network support is pro­vided for 10 and 100 Mbit networks, each in full-duplex and half-duplex mode.

Furthermore, the CP 243-1 supports the "Auto Negotiation" function for the auto­matic negotiation of the mode and the transmission rate to be used. The mode and
the transmission rate can also be defined by the user when configuring the
CP 243-1. If the CP 243-1 was not provided with a valid configuration, it always
uses the “Auto Negotiation“ mode by default.

Note

The Auto Negotiation mode only operates if all connected network components
support this mode.

Industrial Ethernet and TCP/IP do not permit time-deterministic data flows. It can­not be predicted at what time a remote CPU will execute the requested commands.
The responses from the remote CPU are asynchronous to the CPU cycle of the lo­cal CPU. Therefore, TCP/IP-based communication has only limited suitability for
distributed applications with time-related requirements (e.g. control loop, periodic
sampling).

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S7 communication

The S7 services, XPUT and XGET, are used for data exchange between two con­trollers. Here, the CP 243-1 can be implemented as both a client and a server.

Communication between a CP 243-1 and an OPC server running on a PC/PG is
based on the S7 services, READ and WRITE. In this case, the CP 243-1always
acts as the server. Other S7 services, such as the service that automatically que­ries which objects are currently present in an S7-200 (DBs, ...), are not supported.

The following data types or data areas are supported by the CP 243-1:

CP 243-1 as client:

Read and write access:

• The data type is always BYTE

• Only variables can be accessed on the local system.

• The memory areas that are accessible on the partner system when an S7-200

is acting as a partner are inputs, outputs, flags and variables.

• The memory areas that are accessible on the partner system for an S7-300 or
an S7-400 are inputs, outputs, flags and data areas.

CP 243-1 as server:

Write access:

• The data type is BOOL, BYTE, WORD or DWORD

• Accessible memory areas on the local system are inputs, outputs, variables,

flags and status bits.

Read access:

• The data type is BOOL, BYTE, WORD or DWORD

• Accessible memory areas on the local system are inputs, outputs, variables,

flags, system areas and status bits.

Communication with STEP 7 Micro/WIN 32

The CP 243-1 is always the server for communication between a CP 243-1 and
STEP 7 Micro/WIN 32. In this case, STEP 7 Micro/WIN 32 always acts as client.

I/O bus communication

All data areas of the S7-200 CPU can always be accessed. Read and write access
is independent of whether the CPU is in the RUN, TERM or STOP state.

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2.3 Security

2.3.1 Configuration

The CP 243-1 configuration is stored in the S7-200 CPU as non-volatile data. The
validity of the configuration is ensured using a CRC mechanism.

When a CP 243-1 configuration is stored, STEP 7 Micro/WIN 32 calculates a CRC
checksum. This checksum is stored together with the configuration. When the CP
243-1 reads out the configuration, it checks this checksum and in this way can rec­ognize unintentional changes to the stored configuration data.

This CRC mechanism can also be disabled. The configuration can then be
changed either manually or from an S7-200 user program.

Attention

The CP 243-1 cannot completely check the configuration data for consistency with
regard to intentional and unintentional changes after the CRC check has been
switched off. In this case, therefore, there is no guarantee whatsoever that the
CP or the components connected in the network will function correctly.

Attention

The CP 243-1 recognizes that the CRC is disabled when a certain byte in its con­figuration is set to a particular value. If precisely this value should happen to be set
in the configuration, either intentionally or unintentionally, the CRC check will be
disabled. Therefore, it is strongly advised that the configuration be generated with
the Ethernet Wizard integrated in the STEP 7 Micro/WIN 32, and that the S7-200
program be checked for memory operations running in the data area in which the
CP 243-1 configuration data are stored.

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2.3.2 Data security

The CP 243-1 represents a physical connection between Ethernet and the S7-200
I/O bus. Therefore, it offers:

• no protection against intentional or unintentional manipulation of data areas
and/or system status of the local or remote CPUs

• no firewall functionality

Therefore, we recommended that it be used exclusively within local Intranets that
are shielded from the public network by appropriate security mechanisms.

The CP 243-1 terminates an active STEP 7 Micro/WIN 32 connection if no STEP 7
Micro/WIN commands have been sent to the CPU for 60 seconds. This prevents
the Micro/WIN server in the CP 243-1 from remaining blocked due to network faults
and hindering a reconnection with STEP 7 Micro/WIN.

Note

The CP 243-1 allows server access to the S7-200 CPU, both in RUN and STOP
mode of the CPU. However, the program variables or peripheral values are not up­dated in the STOP mode.

2.3.3 Integrity of communication

The CP 243-1 is equipped with a life-signs monitoring mechanism ("Keep
Alive" mechanism). With the aid of this mechanism, the CP 243-1 is able to auto­matically detect, within a configurable time period, that a communications partner
or the associated connection has failed.

The Keep Alive time specified when configuring the CP 243-1 is the time period af­ter which internal mechanisms that attempt to reach the communications partner
are started. Processing of these mechanisms takes approx. 10 seconds. If the
communications partner cannot be reached within this time period, the CP243-1
automatically terminates the connection to this partner. If the CP 243-1 was being
operated as a client, it then attempts to re-establish this connection. The user is
notified of the failure of a communications partner by the mechanisms described in
Chapter 6.

In general, you should activate the Keep Alive mechanism in all system involved in
communication, provided these system are equipped with such a mechanism.

Note

For the Keep-Alive mechanism to function, this mechanism must also be supported
by the communications partner in accordance with RFC1122 and RFC793.

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2.4 Connections

Front view:

Integrated ribbon cable
with socket for I/O bus

Connector

for I/O bus

8-pin RJ45 socket for
Ethernet connection

Fig. 2. Connections

The CP 243-1 has the following connections:

• Terminal block for 24 V DC supply voltage and ground connection

• 8-pin RJ45 socket for Ethernet connection

• Plug connector for I/O bus

• Integrated ribbon cable with socket for I/O bus

The connections are located underneath the covers of the front doors.

Terminal block for 24 V DC supply
voltage and ground connection

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2.5 Displays: Front LEDs

Fig. 3. Front with LED displays

Five LEDs are located on the front to indicate:

LED display Color Meaning

SF

LINK Green, continuous

RX/TX Green, flickering Ethernet activity:

Red, continuous

Red, flashes

System error:
Lights up when an error occurred

System error:
Flashes (approx. every second), if the configuration
is faulty and a BOOTP server cannot be found.

Connection via the RJ45 interface:
Ethernet connection has been established

Data are being received and transmitted via the
Ethernet

Note:

A packet received via the Ethernet is not necessarily
intended for the CP 243-1. The CP 243-1 initially
accepts every packet transmitted on the Ethernet.
Only then does it decide whether the package is in­tended for it.

The RX/TX LED also flashes as soon as the
CP 243-1 attempts to send a packet if the Ethernet
cable has been unplugged.

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LED display Color Meaning

RUN Green, continuous

CFG Yellow, continuous

Operational:
The CP 243-1 is ready for communication

Configuration:
Lights up when STEP 7 Micro/WIN 32 actively main­tains a connection to the S7-200 CPU via the CP
243-1

Table 1: Functions of individual LED displays

While the CP243-1 is booting, the SF LED blinks twice. Then, the LINK LED and
the RX/TX LED blink several times. As soon as the RUN LED lights up, the
CP 243-1 has finished booting.

CP 243-1
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Installation and commissioning 09/02

3 Installation and commissioning

Installation

The devices of the S7-200 series can be installed either in a control panel or on a
DIN rail. The modules can be arranged both horizontally and vertically. The
S7-200 CPU and the extension modules are designed to naturally dissipate heat
by means of convection. Therefore, leave a space of at least 25 mm both above
and below the device to ensure adequate heat dissipation. Long operating times at
maximum ambient temperature and maximum load shorten the operating life of the
electronic components.

Note

The position in an S7-200 system in which a CP 243-1 can be operated depends
on the firmware version of the S7-200 CPU.

When using firmware version 1.2 or higher, the CP 243-1 can be installed in any
position in an S7-200 system. For firmware versions below version 1.2, the
CP 243-1 must be installed directly next to the S7-200 CPU.

Wiring

!

Warning

If you attempt to install or remove the CP 243-1 or other devices with the
equipment switched on, you may receive an electric shock or the devices may
not operate properly.

If the power supply for the CP 243-1 and all connected devices is not switched
off while the devices are being installed or removed, this may result in personal
injury and/or damage to equipment.

Take all necessary safety precautions and ensure that the power supply for the
S7-200 and the CP 243-1 has been switched off before wiring the system.

CP 243-1

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09/02 Installation and commissioning

General guidelines

General guidelines to follow when wiring your automation system:

• Ensure that all applicable and binding standards are complied with when wiring
the CP 243-1. Observe the appropriate national and regional regulations when
installing and operating the device. Inquire at local authorities regarding stan­dards and regulations that must be complied with in your particular case.

• Wire the S7-200 CPU and the CP 243-1 in a de-energized state only!

• Use cables with a cross section appropriate for the current in each case. The

24 V supply of the CP 243-1 can be wired with cables with a cross section be­tween 0.50 mm² and 1.50 mm². For wiring ground terminals, use cables with a
diameter of 1.50 mm².

• Do not tighten the connecting terminals excessively. The maximum permissible
torque is 0.56 Nm.

• Always lay the cables over as short a distance as possible. Cables should be
laid in pairs: a neutral conductor together with a phase conductor or signal ca­ble.

• Separate AC wiring and high-voltage DC wiring with rapid switching sequences
from low-voltage signal wiring.

• Provide cables at risk of being struck by lightning with a suitable surge protec-
tion.

• The S7-200 CPU and the CP 243-1 should be connected to the same power
supply!

• The CP 243-1 is supplied with an integrated ribbon cable with a connector
socket for quick connection to other S7-200 components.

• The firmware version of the S7-200 CPU in use dictates in which slot a
CP 243-1 can be operated (see note on page 20).

• A maximum of one CP 243-1 can be used per CPU.

CP 243-1
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