The SIMATIC S7-1200 is the new modular industrial controller intended for small and medium applications. While designing the new system the main emphasis was put on making the communication between the SIMATIC HMI operator panels and the SIMATIC S7-1200 controllers as efficient as possible, in regard to data transfer as well as ease and intuitiveness of application design. It is especially visible at variables management in the application design. The system allows a single declaration of variables for the visual and the controller part of the design.

It also allows for a free transfer of variables between devices being designed - all within one design database. Thanks to this solution, many application errors may be avoided.

Characteristics of the S7-1200:

• Modular construction: on the left side of the CPU there are CP communication modules, on the right side - binary input/output and analog SM extensions. There is a connection available for the installation of a signal plate module in two variants - as a binary input/output and as an analog output;
• Maximum configuration: 3 communication modules, 8 signal extension modules, 1 signal plate;
• Integrated PROFINET/ETHERNET interface;
• Maximum number of binary input/outputs: 284;
• All P type inputs - active state "1"  (sink) and M - active state "0" (source);
• Maximum number of analog input/outputs: 51;
• 2 integrated 0-10V DC analog inputs;
• Possibility to build decentralized control structures based on PROFINET/ETHERNET, MODBUS RTU, USS networks;
• No moving mechanical parts (ventilators);
• Integrated communication with HMI Basic Panel Industrial Ethernet panel;
• SIPLUS version with a broadened temperature range from 25°C to +70°C;
• Integrated technological functions of fast counters, PID regulation, PWM/PTO output (100kHz) and PLCopen Motion Control;
• Integrated real time clock;
• Possibility of firmware change and upgrade;
• Software operation, diagnostics and modification through an integrated ETHERNET port;
• Extendible terminal strips for signal cables from for all modules.

Mechanical construction

There is a rich spectrum of central CPU units for the SIMATIC S7-1200 controller family, which can be chosen based on the type of electric current (AC or DC) or on the type of integrated outputs in the controller (relay or transistor outputs). From the perspective of efficiency and upgradeability there are three CPU units available, each in three variants of equipment. They vary in terms of memory capacity, the number of inputs/outputs, the number of possible extension modules connected.

It is possible to connect a maximum of 8 extension modules, one signal plate installed directly onto the CPU and 3 communication modules to the SIMATIC S7-1200 CPU 1214C controller. Every CPU unit of the SIMATIC S7 1200 controller has 2 integrated analog outputs with a DC range of 0-10V. The controllers are equipped with technological functions of counting, measurement, adjustment and Motion Control movement which are hardware integrated in the controller.

The SIMATIC S7-1200 controller is equipped with a PROFINET/ETHERNET communication link which supports numerous protocols: TCP/IP, ISO on TCP and S7.

The communication link may be used for programming the controller, communicating between controllers and communication with SIMATIC HMI Basic Panels. All modules have the same dimensions regardless of their number of channels; their width is 45 mm, which allows easy installation in tight spaces.

Functionality

For point to point type communication solutions there are currently two communication modules available: with the RS-485 or RS-232 port, installed on the left side of the central unit. They allow to create own communication protocols in Freeport mode, the use of ASCII protocols, the use of MODBUS RTU or USS protocols for communication with SINAMICS or MICROMASTER inverters. Thanks to this the controller can support bar code readers, printers, communicate with PCs, analog and GSM modems and various drives. Thanks to integrated STEP7 Basic software and PLCopen libraries it is possible to control stepper motors or servo-motors. In order to do this, the PTO impulse outputs (frequency adjustment at given impulse length) up to 100 kHz are used. With the help of the program creator the given velocity profiles with a passage characteristic are created and in the case of using stepper motor control, passage reference points are also declared. Thorough technical knowledge is not required in order to execute stepper motor or servo-motor control. The SIMATIC S7-1200 controller allows the use of 16 PID regulators simultaneously. It is possible to scale the regulator in °C for temperature measurement processes or in bars, in the case of pressure regulation. One may also chose the scaling unit manually.

Communication

The SIMATIC S7-1200 controller has wide communication capabilities:

Industrial PROFINET/ETHERNET - (IEE 802-3 and 802u) with support for TCP/IP, ISO on TCP (RFC 1006), S7

MODBUS RTU master/slave USS protocols - communication with MICROMASTER/SINAMICS inverters.

ASCII Freeport mode and other protocols defined by the user.

New communication modules and protocols are planned to be introduced soon.

Programming

New SIMATIC STEP7 Basic engineering software allows the programming of SIMATIC S7-1200 controllers as well as SIMATIC HMI Basic Panels. The structure of the program windows was divided in order to most efficiently use the space to create the user's program. On the left side of the window, where the program proper is being created, is the application design structure in which HMI and PLC designs are placed in the form of a tree along with additional functions of quick switching to the network link declaration window, changing to "online" direct controller connection mode, additional memory card access or the possibility to introduce a new device to the design. On the right side of the user's program window there is a library of functions available in the program with tabs providing detailed information on every function. Such a structure allows quick and easy access to all parts of the design important at the given moment.

The entire structure of communication connections between devices with declared connections is visible in the declared network part. The STEP7 Basic softwar is integrated on the TIA Portal platform which supports the new functionality between applications. This makes it possible to freely move the variables along with the properties assigned to them between HMI and PLC designs. You may create custom libraries of any chosen elements and objects from the design - design variables as well as most frequently used program functions or object graphics. Additionally it is possible to graphically move variables and symbols between design editors or insert variables by moving them onto previously placed objects in the design using the mouse.

The editors support symbolic variables, so changing the symbolic name in one place of the design will result in changing that name anywhere that variable was placed. The editors are equipped with an array of other interesting solutions optimizing application creation. Design library elements such as blocks, variables, alarms, HMI screens, program blocks, complete HMI or PLC stations are archived in the form of libraries. These library elements, as well as entire libraries can be moved within the same design or can be copied onto other designs. This saves considerable amounts of time on creating applications as well as allows creating custom project libraries which can be later used while creating and starting up your own automation designs.

The library structure is also used by program creators called wizards whose task is to graphically present more complex terms, such as parametrization and designing PID regulators, velocity profile declarations and shaping the movement of Motion Control libraries. The proven concept of Function Blocks and Data Blocks from SIMATIC S7-300/S7-400 systems was transferred onto the SIMANTIC S7-1200 platform. New program editors and the range of improvements related to the TIA Portal concept resulted in the creation of an extremely efficient automation system.