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Entry type: Product note Entry ID: 109801217, Entry date: 10/21/2021

Communication Node SIMATIC CN 4100

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The innovative communication node SIMATIC CN 4100 is a flexible and powerful platform for all communication tasks. Thanks to its scalable, modular structure and the option of connecting third-party systems, the SIMATIC CN 4100 can be used to implement efficient system concepts for process control technology.

Redundant components increase system availability and reduce downtimes. With the option of single or redundant operation, the communication node offers a high degree of flexibility for every application.

1. Product description

1.1 System properties

  • Redundant 24 V DC power supply
  • Hot swapping during operation (with redundant station)
  • Module expansion during operation
  • Fanless design
  • Temperature range -30 °C to +60 °C

1.2 Communication

The SIMATIC CN 4100 can be connected to the Industrial Ethernet bus system via the integrated ethernet interfaces.

Connectivity to a SIMATIC PCS 7 AS-410 is established via the system bus via interfaces X1 and X2 of the CN 4100. The data exchange between 
CN 4100 and S7-410 takes place via S7 communication with the PUT/GET service. The two other interfaces are used to connect OPC UA servers and/or MODBUS/TCP devices.

The assignment of the interfaces is as follows:

A singular SIMATIC CN 4100 station uses the X1.x interfaces. In the redundant configuration, the X2.x interfaces are also used for the second CPU module.

1.3 Integration

Singular structure with OPC UA und MODBUS/TCP:

Redundant structure with MODBUS/TCP:

Redundant structure with MODBUS/TCP redundant and:

System connection SIMATIC PCS 7:

  • User-friendly commissioning with CNET (CN Engineering Tool)
  • Integration in SIMATIC PCS 7 with CN 4100 block library

1.4 Security

Due to an integrated firewall, there is no connection between the system bus interfaces (X1 and X2) and the lower-level networks that are connected via the other interfaces (e.g. OPC UA server, MODBUS/TCP devices).

There is no routing between the networks.

2. Structure

The SIMATIC CN 4100 consists of the following components:

CPU module

The CPU module is the central module of the SIMATIC CN 4100.  All operations and communication tasks are carried out by the CPU.  For each CPU there is one interface for the connection to the plant bus and two separate interfaces for the connection to the end devices (e.g. OPC UA server or MODBUS TCP device)

The SIMATIC CN 4100 can be operated singularly as well as redundantly.

The redundant configuration of the SIMATIC CN 4100 offers significantly higher availability. It works according to the 1-of-2 principle, whereby in the event of an error the active CPU is switched to the backup CPU.

You can also set up the power supply redundantly for each subsystem.

The following protocols are currently supported singularly/redundantly:

Singular configuration (1x CPU):

  • OPC UA DA client
  • S7 communication (PUT/GET)

Redundant configuration (2x CPUs)

  • S7 communication (PUT/GET)

In the redundant configuration, OPC UA is currently only possible singularly with CPU 1 or CPU 2. The OPC UA DA client only establishes a connection to an OPC UA server.

The SIMATIC CN 4100 rack offers connection options for 2x CPU modules and 2x communication modules. The integrated Ethernet interfaces provide the connectivity. The rack is installed by screwing it onto a mounting plate in the control cabinet.

X1.x interfaces are assigned to CPU1, X2.x interfaces are assigned to CPU2.

3. Documentation

  • Sales and limited delivery release 109801218 
  • CN Engineering Tool (CNET) manual 109802239 


5. Approvals

SIMATIC CN 4100 fulfills the current national and international standards:

6. Order data

ProductDescriptionArticle number

SIMATIC CN 4100 rack 4 slot


  • 6x Ethernet
  • 2x USB
  • 2x 24V DC

SIMATIC CN 4100 CPU module


  • OPC UA client
  • S7 PUT/GET

 Paper license MODBUS/TCP for 1x CN 4100 CPU module
 OSD license MODBUS/TCP for 1x CN 4100 CPU module
 Paper license OPC UA client for 1x CN 4100 CPU module
 OSD license OPC UA client for 1x CN 4100 CPU module
Security information
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