Configuring Communication Connections

4.6.3TCP with the FETCH/WRITE Mode

Using FETCH PASSIVE / WRITE PASSIVE

If you select one of the FETCH PASSIVE or WRITE PASSIVE modes for the TCP connection, you can access the system areas on a SIMATIC S7 PLC from a SIMATIC S5 station or other non-S7 station.

Figure 4-21

The connection can then only be used for this mode; sending or receiving with the FCs AG_SEND/AG_LSEND or AG_RECV/AG_LRECV is then no longer possible.

The connection establishment is passive; in other words, only the partner station (SIMATIC S5 station or other non-S7 station) can establish the connection. The setting is made automatically in the “General” tab and cannot be changed.

SFETCH

If you select the FETCH mode, you allow direct read access to system memory on the SIMATIC S7 PLC. Such access can be, for example, from a SIMATIC S5 station or other station.

SWRITE

If you select the WRITE mode, you allow direct write access to system memory on the SIMATIC S7 PLC. Such access can be, for example, from a SIMATIC S5 station or other station.

SIMATIC NET NCM S7 for Industrial Ethernet

125

C79000-G8976-C129–06

Page 125
Image 125
Siemens S7 appendix TCP with the FETCH/WRITE Mode, Using Fetch Passive / Write Passive

S7 specifications

The Siemens S7 series represents a cornerstone in the realm of programmable logic controllers (PLCs), developed by Siemens, a leading company in industrial automation. Widely used across various industries, the S7 series offers robust solutions for controlling machinery and processes, thanks to its reliable performance, flexibility, and scalable architecture.

One of the key features of Siemens S7 PLCs is the modularity of their design. Each system can be configured to meet specific application requirements due to the ability to mix various input/output modules, CPUs, and communication processors. This modular approach allows for the customization of systems to suit diverse automation tasks, providing end users with the adaptability required for modern manufacturing environments.

The S7 series encompasses several models, including the S7-1200, S7-300, and S7-1500. The S7-1200 is particularly suited for small to medium-sized applications, offering a compact design and integrated communication interfaces. In contrast, the S7-300 is designed for more extensive and complex control systems, making it ideal for large-scale industrial applications. The S7-1500 stands out with its advanced performance metrics, rich feature set, and high-speed processing capabilities, making it perfect for demanding applications that require real-time control and extensive data handling.

Siemens also emphasizes the importance of communication technologies within the S7 series. With options such as PROFINET, PROFIBUS, and EtherNet/IP, the S7 PLCs can seamlessly integrate into existing automation infrastructures, ensuring smooth data exchange between devices. The incorporation of web-based technologies and cloud connectivity further enables remote monitoring and control of systems, enhancing operational efficiency.

Another notable characteristic of Siemens S7 PLCs is the use of TIA Portal (Totally Integrated Automation Portal), an innovative software platform that simplifies the engineering process. TIA Portal allows users to program, configure, and diagnose their automation devices in a single environment, reducing setup times and improving productivity.

In conclusion, the Siemens S7 series stands out due to its modular design, range of models suitable for various applications, advanced communication technologies, and user-friendly programming software. This combination of features and characteristics makes S7 PLCs a preferred choice for industries seeking reliable and efficient automation solutions. As industrial demands continue to evolve, Siemens S7 PLCs remain at the forefront, adapting to technological advancements and setting benchmarks in the automation field.