ILMU AUTOMATION

Configuration Notes:
Please note the following points if you wish to connect a SIMATIC HMI operator panel to an ET 200-CPU:

Properties of the ET 200-CPUs

• ET 200S CPU:
  The IM151-7 CPUs of ET 200S have an MPI/ DP interface:
  In the MPI subnetwork you can use the HMI operator panel to operate the ET 200S CPU via the integrated MPI interface.
  On the PROFIBUS DP the integrated DP interface of the ET 200S CPU can only be used as a DP slave, i.e. in addition to the HMI operator panel you need a DP master (e.g. S7-300 CPU316-2DP) that operates the IM 151-7 CPU as a DP slave.
  
  If the IM151-7 CPU is operated without DP master on the PROFIBUS DP, communication with the HMI operator works, but a bus error is displayed on the IM151-7 CPU.
  
  Note:
  With the DP master module (order number: 6ES7138-4HA00-0AB0), which you slot directly next to the ET 200S CPU, you can add a DP interface to the ET 200S, which is configured as DP master. With this master interface module it is then possible to operate the ET 200S without any other DP master on the PROFIBUS DP.
  
  Requirements:
  In order to be able to use the DP interface on the master interface module you require a CPU, order number 6ES7151-7AA10-0AB0, and firmware version V2.1 or higher.
  
  
• ET 200X CPU:
  The BM147-1 CPUs of ET 200X have an MPI/ DP interface:
  In the MPI subnetwork you can use the HMI operator panel to operate the ET 200X CPU via the interface parameterized as MPI.
  On the PROFIBUS-DP the ET 200X CPU (BM 147-1) can only be used as a DP slave, i.e. in addition to the HMI operator panel you need a DP master (e.g. S7-300 CPU316-2DP) that operates the BM 147-1 as a DP slave.
  
  The BM147-2 CPUs of ET 200X have an MPI/ DP interface that can be parameterized as MPI or as a DP slave, and another DP master interface.
  In the MPI subnetwork you can use an HMI operator panel to operate the ET 200X CPU via the interface parameterized as MPI.
  On the PROFIBUS DP the ET 200X CPU BM 147-2 can operate on the one hand as a DP slave with an additional DP master (e.g. an S7-300 CPU 315-2DP). On the other hand the BM147-2 CPU can also communicate as DP master with the HMI operator panel via the DP master interface.

Warning:
The ET 200-CPU is configured in the SIMATIC Manager in a
SIMATIC S7-300 station.

Options for connecting an HMI operator panel to the ET 200 CPUs

• Connecting the HMI operator panel via MPI to the ET 200 CPU
• Connecting the HMI operator panel via PROFIBUS DP to the ET 200 CPU
• Connecting the HMI operator panel (MPI) via routing (CPU 316-2DP: DP master) to the ET 200 CPU (DP slave)
• Overview: HMI operator panel with ET 200 CPU

Connecting the HMI operator panel via MPI to the ET 200 CPU
You can connect the HMI operator panel via MPI directly to an IM151 CPU or BM147 CPU.

( 7 KB )
Fig. 1: HMI station connected to ET 200S CPU via MPI

Setting in the STEP 7 Hardware Configuration
In the Properties dialog of the MPI/DP interface of the ET 200 CPU you set the type of interface to MPI and then connect the station to the MPI subnetwork.

( 11 KB )
Fig. 2: ET 200 CPU connected to MPI

Settings in the STEP 7 Hardware Configuration of the SIMATIC HMI station
Double-click the HMI MPI/DP interface of the HMI station and network this via MPI with the ET 200 CPU.

( 28 KB )
Fig. 3: HMI station networked with MPI

Enabling the connection in WinCC flexible ES
Open the HMI station with WinCC flexible ES. Under Communication > Connections you enable the connection already created to the ET 200 CPU.

Note:
The "Cyclic operation" option must be deselected.

( 81 KB )
Fig. 4: Enabling the connection in WinCC flexible

Connecting the HMI operator panel via PROFIBUS DP to the ET 200 CPU

1. Version: CPU 316-2DP as DP master, ET200 CPU as DP slave
2. Version: ET200S CPU with DP master module

1. Version: CPU 316-2DP as DP master, ET200 CPU as DP slave

The ET 200 CPU is operated as DP slave on the PROFIBUS DP subnetwork, i.e. in addition to the HMI operator panel and the ET 200 CPU (IM151 CPU or BM147 CPU) you need a DP master (e.g. S7-300 CPU 316-2DP) on the PROFIBUS DP subnetwork.

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Fig. 5: HMI station connected to ET 200 CPU via PROFIBUS DP

Settings in the STEP 7 Hardware Configuration of the ET 200 CPU for supporting ALARM_S messages
In order for the ET 200 CPU to support the ALARM_S service, in the Properties of the DP interface of the IM151 CPU or BM147 CPU under Operating Mode you must enable the option Test, commissioning, routing.

( 11 KB )
Fig. 6: Enabling "Test, commissioning, routing"

Settings in the STEP 7 Hardware Configuration of the S7-300 DP master
Once you have networked the ET 200 CPU with PROFIBUS DP, open the Hardware Configuration of the DP master station (CPU 316-2DP) and there you configure the ET 200 CPU as a DP slave.

( 12 KB )
Fig. 7: ET 200 CPU as DP slave

Settings in the STEP 7 Hardware Configuration of the SIMATIC HMI station
Double-click the HMI MPI/DP interface of the HMI station and network it with the ET 200 CPU via PROFIBUS.

( 26 KB )
Fig. 8: HMI station networked with PROFIBUS

Enabling the connection in WinCC flexible ES
Open the HMI station with WinCC flexible ES. Under Communication > Connections you enable the connection already created to the ET 200 CPU.

Note:
The "Cyclic operation" option must be deselected.

( 83 KB )
Fig. 9: Enabling the connection in WinCC flexible

2. Version: ET200S CPU with DP master module

The ET 200S is operated with the DP master interface module as DP master on the PROFIBUS DP. The HMI operator panel is connected to the master module via PROFIBUS.

( 9 KB )
Fig. 10: HMI operator panel connected to DP master module via PROFIBUS DP

Settings in the STEP 7 Hardware Configuration
Network the DP master module of the ET 200S with a newly created PROFIBUS network.
The master interface module is located in the Hardware Catalog in the project tree from which you configured the IM151-7 CPU.

( 13 KB )
Fig. 11: DP master module connected to ET200S

Settings in the STEP 7 Hardware Configuration of the SIMATIC HMI station
Double-click the HMI MPI/DP interface of the HMI station and network it with the DP master module of the ET 200 CPU via PROFIBUS.

( 27 KB )
Fig. 12: HMI station networked with PROFIBUS

Enabling the connection in WinCC flexible ES
Open the HMI station with WinCC flexible ES. Under Communication > Connections you enable the connection already created to the ET 200 CPU.

Note:
The "Cyclic operation" option must be deselected.

( 79 KB )
Fig. 13: Enabling the connection in WinCC flexible

Connecting the HMI operator panel (MPI) via routing (CPU 316-2DP: DP master) to the ET 200 CPU (DP slave)
The ET 200 CPU (IM151 CPU or BM147 CPU) is operated as a DP slave on an S7-300 CPU 316-2DP (DP master). The HMI operator panel is connected to the S7-300 via MPI. Via routing (MPI <-> PROFIBUS DP) a connection is set up between the HMI operator panel and the ET 200 CPU.

( 10 KB )
Fig. 14: HMI operator panel connected to the ET 200 CPU via routing

Settings in the STEP 7 Hardware Configuration of the ET 200 CPU for supporting ALARM_S messages
In order for the ET 200 CPU to support the ALARM_S service, in the Properties of the DP interface of the IM151 CPU or BM147 CPU under Operating Mode you must enable the option Test, commissioning, routing.

( 11 KB )
Fig. 15: Properties of the DP interface

Settings in the STEP 7 Hardware Configuration
Once you have networked the ET 200 CPU with PROFIBUS DP, open the Hardware Configuration of the DP master station (CPU 316-2DP) and there you configure the ET 200 CPU as a DP slave. The S7-300 station must also be networked with MPI.

( 12 KB )
Fig. 16: ET 200 CPU as DP slave

Settings in the STEP 7 Hardware Configuration of the SIMATIC HMI station
Double-click the HMI MPI/DP interface of the HMI station and network it with the DP master module of the S7 -300 CPU (CPU 316-2DP) via MPI.

( 28 KB )
Fig. 17: HMI station networked with MPI

Enabling the connection in WinCC flexible ES
Open the HMI station with WinCC flexible ES. Under Communication > Connections you enable the connection already created to the ET 200 CPU.

( 80 KB )
Fig. 18: Enabling the connection in WinCC flexible

Note:
The "Cyclic operation" option must be deselected.

Overview: HMI operator panels with ET 200 CPU

Note:
More information on configuring Alarm_S messages and the display on the operator panel is available in the Support Shop in Entry ID: 24013249.

How do you program the communication blocks FB63 "TSEND", FB64 "TRCV", FB65 "TCON" and FB66 "TDISCON" in order to use the ISO-on-TCP protocol for data exchange via the integrated Industrial Ethernet interface of an S7-300 or S7-400 CPU or via the CP443-1 Adv?

Description:
You can use the open communication via Industrial Ethernet for data exchange via the integrated Industrial Ethernet interface of a CPU. The following protocols are supported for this:

• TCP
• ISO-on-TCP
• UDP

The following communication blocks are available for open communication via Industrial Ethernet using ISO-on-TCP Protocol:

• FB65 "TCON" for establishing the connection
• FB66 "TDISCON" for ending the connection
• FB63 "TSEND" for sending data
• FB64 "TRCV" for receiving data

These communication blocks are available in the Standard Library -> Communication Blocks. The connection parameters for establishing the ISO-on-TCP connection are saved in a data structure. In this example, the data structure UDT65 "TCON_PAR" is used, which is parameterized by the user. The ISO-on-TCP connection is not configured in NetPro.

Note:
Detailed information on open communication via Industrial Ethernet is available in the manual "System Software for S7-300/400 System and Standard Functions" in Entry ID: 1214574.

Description of the sample program
The S7 program contains the call of the FB65 "TCON" and the data structure UDT65 "TCON_PAR" with the connection parameters for establishing the ISO-on-TCP connection. The S7 program also includes the call of the communication blocks FB63 "TSEND" and FB64 "TRCV" from the Standard Library -> Communication Blocks. The FB63 "TSEND" is for sending data to an S7 station or to an S5 station, to a PC station or to a third-party system. The FB64 "TRCV" is for receiving data from another S7 station or an S5 station, from a PC station or from a third-party system.

First create the hardware configuration for your S7-300 station. Note that you configure marker byte 10 as clock marker. The send request is triggered by this clock marker. Save and compile the hardware configuration of your S7-300 station and load it into the CPU.

The STEP 7 program consists of blocks OB100, OB1, FB400, DB400, FB420, UDT65 and FB63, FB64, FB65 and FB66.

OB100:
OB100 is a restart OB and is run when the CPU is restarted (warm start). In this OB, the first communication trigger is enabled with marker 0.3 "START-UP".

OB1:
OB1 is called cyclically. FB400 is called in this OB (instance data block: DB400) with M0.3 "START-UP" as parameter (INIT_COM). The M0.3 "START-UP" is reset at the end of OB1.

Fig. 01: OB1

FB400:
FB400 is called in the OB1 cycle. In this FB, you find the call of the FB420 "T_ISO-ON-TCP_IDB" and of blocks FB65 "TCON", FB63 "TSEND", FB64 "TRCV" and FB66 "TDISCON".

The local and remote parameters of the ISO-on-TCP connection are set via FB420 "SET_ENDPOINT". This concerns the following parameters:

• ID: Connection ID
• DEV_ID
  DEV_ID = B#16#0 for the CP443-1 Adv
  DEV_ID = B#16#1 for the IM151-8 PN/DP CPU or
  DEV_ID = B#16#2 for the CPU31x-2PN/DP, IM154-8 CPU or
  DEV_ID = B#16#3 for the CPU319-3PN/DP or
  DEV_ID = B#16#5 for the CPU41x-3PN/DP
• ACTIVE: Connection established actively or passively
• TSAP: Local TSAP in the CPU and remote TSAP of the communication partner
• IP_ADDR1 ... IP_ADDR4: IP address of the communication partner

Fig. 02: Calling FB420

Note:
The ISO-on-TCP connection requires the two leading bytes E0.02 for the local TSAP (connection endpoint) in a CPU31x-2PN/DP or CPU319-3PN/DP. Rack and slot of the CPU define the specification "02" in the leading bytes of the TSAP. You define this local TSAP as remote TSAP in the communication partner. The following TSAPs are configured in this example:

In the interface parameterization, you change the value of the local and remote TSAP in accordance with your configuration.

Fig. 03: FB400 interface parameterization

Establishing connection is started by a positive edge in the input parameter "REQ" of the FB65 "TCON". The data structure UDT65 "TCON_PAR" with the connection parameterization is incorporated in the instance data block of the FB400. On the input parameter "CONNECT" of the FB65 "TCON", the memory area is specified that contains the connection parameterization.
The connection is set up at system start and remains until it is disabled with FB66 "TDISCON", the CPU goes into STOP mode, or the electricity supply is switched off.

Fig. 04: Calling FB65 "T_CON"

The send request is triggered via a positive edge on the input parameter "REQ" of the FB63 "TSEND". The send job trigger is controlled by clock marker M10.6 and the variable "C1.SEND_BUSY". If the send job is running, "C1.SEND_BUSY" is set. Triggering a new send job is not then possible (see Fig. 06).
You specify the memory area that contains the data to be sent on the input parameter "DATA". You enter the number of bytes to be sent for the input parameter "LEN". The output parameters "DONE", "ERROR" and "STATUS" are required for job evaluation.

Fig. 05: Calling FB63 "TSEND"

If the send job is successfully completed, "C1.SEND_BUSY" is reset. A new send job can now be triggered.

If the send job is completed with an error, then "C1.SEND_BUSY" is likewise reset and the value of the output parameter "STATUS" of the FB63 is saved for error analysis.

Fig. 06: Positive edge for triggering send job / resetting "C1.SEND_BUSY"

Fig. 07: Saving output parameter STATUS of the FB63 "TSEND"

The data can be received as soon as the ISO-on-TCP connection is established. On the input parameter "DATA", you specify the address and length of the data area where the received data is saved.

Fig. 08: Calling FB64 "TRECV"

The output parameter "NDR" is for showing that new data has been received. The output parameter "LEN" indicates the length of the data received.
If the data is not successfully received, then the value of the output parameter "STATUS" is saved and evaluated.

Fig. 09: Saving output parameter STATUS of the FB64 "TRECV"

You can disable the ISO-on-TCP connection with the FB66 "TDISCON". You start the request to disable the ISO-on-TCP connection via a positive edge on the input parameter "REQ" of the FB66 "TDISCON".

Fig. 10: Calling the FB66 "TDISCON"

The STEP 7 project for downloading:
The STEP 7 project contains a sample program for calling FB400 and the function blocks FB420 "SET_ENDPOINT", FB65 "TCON", FB66 "TDISCON", FB63 "TSEND" and FB64 "TRECV" with status evaluation. It was created with STEP 7 V5.4 SP3.

Sample_open_ISO.zip ( 48 KB )

Configuring additional ISO-on-TCP connections
To configure additional ISO-on-TCP connections you copy the FB400 so that you receive another function block (such as FB401). Change the parameters and generate a new instance data block.

IMPORTANT!
The sample program is freeware. Any user can use, copy and forward this program FREE OF CHARGE. The authors and owners of this program take no responsibility whatsoever for the functionality and compatibility of this software. Use of the software is at the user's own risk. Since this software is free of charge, there is absolutely no warranty nor entitlement to error correction and hotline support.

How do you program the communication blocks FB63 "TSEND", FB64 "TRCV", FB65 "TCON" and FB66 "TDISCON" in order to use the TCP protocol for data exchange via the integrated Industrial Ethernet interface of an S7-300 or S7-400 CPU?

Description:
You can use the open communication via Industrial Ethernet for data exchange via the integrated Industrial Ethernet interface of a CPU. The following protocols are supported for this:

• TCP
• ISO-on-TCP
• UDP

The following communication blocks are available for open communication using TCP Protocol:

• FB65 "TCON" for establishing the connection
• FB66 "TDISCON" for ending the connection
• FB63 "TSEND" for sending data
• FB64 "TRCV" for receiving data

These communication blocks are available in the Standard Library -> Communication Blocks. The connection parameters for setting up the TCP connection are saved in a data structure. In this example, the data structure UDT65 "TCON_PAR" is used, which is parameterized by the user. The TCP connection is not configured in NetPro.

Note:
Detailed information on open communication via Industrial Ethernet is available in the manual "System Software for S7-300/400 System and Standard Functions" in Entry ID: 1214574.

Description of the sample program
The S7 program contains the call of the FB65 "TCON" and the data structure UDT65 "TCON_PAR" with the connection parameters for setting up the TCP connection. The S7 program also includes the call of the communication blocks FB63 "TSEND" and FB64 "TRCV" from the Standard Library -> Communication Blocks. The FB63 "TSEND" is for sending data to an S7 station or to an S5 station, to a PC station or to a third-party system. The FB64 "TRCV" is for receiving data from another S7 station or an S5 station, from a PC station or from a third-party system.

First create the hardware configuration for the S7-300 station. Note that you configure marker byte 10 as clock marker. The send request is triggered by this clock marker. Save and compile the hardware configuration of your S7-300 station and load it into the CPU.

The STEP 7 program consists of blocks OB100, OB1, FB300, DB300, FC97, UDT65 and FB63, FB64, FB65 and FB66.

OB100:
OB100 is a restart OB and is run when the CPU is restarted (warm start). In this OB, the first communication trigger is enabled with marker 0.3 "START-UP".

OB1:
OB1 is called cyclically. FB300 is called in this OB (instance data block: DB300) with M0.3 "START-UP" as parameter (INIT_COM). The M0.3 "START-UP" is reset at the end of OB1.

Fig. 01: OB1

FB300:
FB300 is called in the OB1 cycle. In this FB, you find the call of the FC97 "SET_TCP_ENDPOINTx" and of blocks FB65 "TCON", FB63 "TSEND", FB64 "TRCV" and FB66 "TDISCON".

The local and remote parameters of the TCP connection are set via the FC97 "SET_TCP_ENDPOINTx". This concerns the following parameters:

• ID: Connection ID
• DEV_ID
  DEV_ID = B#16#1 for the IM151-8 PN/DP CPU or
  DEV_ID = B#16#2 for the CPU31x-2PN/DP, IM154-8 CPU or
  DEV_ID = B#16#3 for the CPU319-3PN/DP or
  DEV_ID = B#16#5 for the CPU41x-3PN/DP
• ACTIVE: Connection established actively or passively
• LOC_PORT: Local port in the CPU
• REM_PORT: Remote port of the communication partner
• IP_ADDR1 ... IP_ADDR4: IP address of the communication partner

Fig. 02: Calling FC97

Establishing connection is started by a positive edge in the input parameter "REQ" of the FB65 "TCON". The data structure UDT65 "TCON_PAR" with the connection parameterization is incorporated in the instance data block of the FB300. On the input parameter "CONNECT" of the FB65 "TCON", the memory area is specified that contains the connection parameterization.
The connection is set up at system start and remains until it is disabled with FB66 "TDISCON", the CPU goes into STOP mode, or the electricity supply is switched off.

Fig. 03: Calling FB65 "T_CON"

The send request is triggered via a positive edge on the input parameter "REQ" of the FB63 "TSEND". The send job trigger is controlled by clock marker M10.6 and the variable "C1.SEND_BUSY". If the send job is running, "C1.SEND_BUSY" is set. Triggering a new send request is not then possible (see Fig. 05).
You specify the memory area that contains the data to be sent on the input parameter "DATA". You enter the number of bytes to be sent for the input parameter "LEN". The output parameters "DONE", "ERROR" and "STATUS" are required for job evaluation.

Fig. 04: Calling FB63 "TSEND"

If the send job is successfully completed, "C1.SEND_BUSY" is reset. A new send job can now be triggered.

If the send job is completed with an error, then "C1.SEND_BUSY" is likewise reset and the value of the output parameter "STATUS" of the FB63 is saved for error analysis.

Fig. 05: Positive edge for triggering send job / resetting "C1.SEND_BUSY"

Fig. 06: Saving output parameter STATUS of the FB63 "TSEND"

The data can be received as soon as the TCP connection is established. On the input parameter "DATA", you specify the address and length of the data area where the received data is saved.

Fig. 07: Calling FB64 "TRECV"

The output parameter "NDR" is for showing that new data has been received. The output parameter "LEN" indicates the length of the data received.
If the data is not successfully received, then the value of the output parameter "STATUS" is saved and evaluated.

Fig. 08: Saving output parameter STATUS of the FB64 "TRECV"

You can disable the TCP connection with the FB66 "TDISCON". You start the request to disable the TCP connection via a positive edge on the input parameter "REQ" of the FB66 "TDISCON".

Fig. 09: Calling the FB66 "TDISCON"

The STEP 7 project for downloading:
The STEP 7 project contains a sample program for calling FB300 and the function FC97 "SET_TCP_ENDPOINTx", the blocks FB65 "TCON", FB66 "TDISCON", FB63 "TSEND" and FB64 "TRECV" with status evaluation. It was created with STEP 7 V5.4 SP3.

Sample_open_TCP.zip ( 45 KB )

Configuring additional TCP connections
To configure additional TCP connections, you copy the FB300 so that you receive another function block (such as FB301). Change the parameters and generate a new instance data block.

IMPORTANT!
The sample program is freeware. Any user can use, copy and forward this program FREE OF CHARGE. The authors and owners of this program take no responsibility whatsoever for the functionality and compatibility of this software. Use of the software is at the user's own risk. Since this software is free of charge, there is absolutely no warranty, no claim for error correction and no hotline support.

Instructions
This entry shows you how to implement chronological messaging with an S7-400 CPU and WinCC. Chronological messaging means that the messages are sent from the PLC to the WinCC station. When they are created in the PLC, the messages are given a time stamp and then sent to the WinCC station. WinCC does not poll the PLC, which significantly reduces the bus load. The following two basic types of message and their configuration are demonstrated in the attached PDF file:

1. Symbol-related messages
   Symbol-related messages can only be generated by CPUs of the S7-400 series. The messages are triggered asynchronously to the program.
2. Block-related messages
   Block-related messages can be generated by CPUs of the S7-300 and S7-400 series.
   The block-related messages are created by the STEP 7 program using the system message blocks (e.g. ALARM_8P). The message is sent as soon as the STEP 7 program calls a system message block and the conditions for sending a message are fulfilled. The messages are triggered synchronously to the program.

More information:

• Reference manual "Programmable Logic Controller S7-400 CPU Data"
  This gives you detailed information on the available message procedures of a CPU. This documentation is part of the documentation package 6ES7498-8AA03-8AA0. The manual is available for downloading in Entry ID 19538001.
• Manual "Operation List S7-400 CPU 412, 414, 416, 417"
  This gives you detailed information on available system functions and system function blocks for creating CPU messages. This documentation is part of the documentation package 6ES7498-8AA04-8AN0. The manual is available for downloading in Entry ID 1117645.
• STEP 7 Online Help
  Detailed information on alarm processes, alarm types and system alarm blocks is available in the STEP 7 Online Help.

Requirements:

• The WinCC component "AS-OS Engineering" is installed.
  You can select this component when doing a user-defined setup of WinCC. Please use the following installation sequence:
  
  1. STEP 7
  2. WinCC with the "AS-OS Engineering" component

  Entry ID 22272911 includes a description of how to retro-install the "AS-OS Engineering" component.
  

• The WinCC project is integrated in the STEP 7 project.
  Entry ID 11841504 contains information on how to integrate a WinCC project in STEP 7.
  
• The "Alarm Logging Runtime" is enabled in the startup list in the "Computer Properties" dialog of the WinCC project.

Below we show you how to configure symbol-related and block-related messages.

WinCC_ZeitfolgeRichtigMeldenS7400 ( 606 KB )

This entry has been created with WinCC V6.0 SP4 and STEP 7 V5.3 SP2. The entry was also tested with WinCC V7.0 and STEP 7 V5.4 SP4.

Configuration Notes:
Please note that not every type or version of adapter supports all the baud rates that can be set on the relevant MPI/PROFIBUS/PPI interface. More information on this is available in the documentation supplied with the product.

The PC/TS/HMI Adapters of the different generations require different power supply voltages. These voltages are supplied to the adapters via the 9-pin D-SUB socket (where the device connector is slotted). But not all the interfaces of the system supplied the voltage required.

The PC/TS/HMI Adapters require the voltages given below for operation:

• Generation 1 adapters:
  HMI Adapter (order number: 6ES7972-0CA1x-0XA0), PC Adapter (order number: 6ES7972-0CA2x-0XA0) and TS Adapter (order number: 6ES7972-0CA3x-0XA0) require both 5V and 24V at the MPI/DP interface.
  
• Generation 2 adapters:
  The PC Adapter USB (order number: 6ES7972-0CB20-0XA0) only requires 24V at the MPI/DP interface.
  
• The TS Adapters II (order numbers: 6ES7972-0CB35-0XA0 and 6ES7972-0CC35-0XA0) only require 24V as power supply. This 24V supply can come either via the DP/MPI interface or via the supply connector of an external power supply source.

The table shows which interface of the automation system can be connected with which adapter with regard to power supply.

Fig. 1: Table of required/available voltages for the PC/TS/HMI Adapters

Note:
The RS232 interface has the following permissible voltage ranges:

• At logic level "0" the voltage level is between +3V and +15V.
• At logic level "1" the voltage level is between -3V and -15V.

If, for example, you use a voltage level of 4V, this is still in the permissible range, but is very close to the limit of the undefined range. Now, if there is power attenuation or very high EMC interference, the result might be that the signal is no longer clearly recognized and after multiple transfer attempts there is a negative acknowledgment of the message. Since the SIMATIC products are designed for industrial application, the voltage values are in the upper range so that there is no interruption in the transfer. More information is available in the Internet in our FAQ "Technical data of the RS232C interface" in Entry ID: 2892960 .