Siemens PLC ---Simatic S7,plc control

S7 PLC controllers: customized expandability

PLCs don’t just perform open-loop control these days, they also handle

• Closed-loop control,
• Positioning,
• Counting, proportioning,
• Valve control and much more.

For this purpose, there are intelligent I/O modules. They are microprocessor-controlled and execute time-critical special tasks completely autonomously, and they have a direct connection to the process via their own input/output channels. This avoids additional loads for the CPU.

Distributed I/Os

If it is necessary to bridge large distances between the process and the I/O modules, the wiring can become very complex and susceptible to faults. If a modular and flexible automation system is required, we recommend use of distributed I/O systems:

• With the distributed I/O system ET 200, remote I/O devices, small control systems and numerous other field devices can be operated remotely from the process location up to a distance of 23 km. The connected devices are interconnected via the fast PROFIBUS DP fieldbus to EN 50 170.

Programming devices, software

The SIMATIC family offers an attractive overall programming devices concept from the low-cost handheld programming devices to the especially powerful desktop programming devices.

And to match these our software. Starting with the operating system:

• Windows NT/2000/XP – for the proven SIMATIC software and for all PC applications
• And our STEP 7 software makes programming your controller quick and simple. A single software package for development, documentation and testing.

Industrial PCs

The rugged industrial PCs of the Siemens S7 range are the ideal tools for acquiring, processing and archiving machine data and process data, for operator control and visualization of material flows and manufacturing sequences, as well as for process control tasks.

Human machine interface

The more complex automated processes become, the more important it is to have human-machine communication suited to the process.

Our range of SIMATIC HMI devices provides the right solution for every task.

Open communication

The productivity of any manufacturing system depends to a great extent on the flexibility of the control systems used. Decentralization means increased flexibility but also an increased need for devices to exchange data with each other and with a host computer.

SIMATIC offers a choice of two solutions for this purpose:

• Direct point-to-point connection from CPU to CPU or via communication processors where only a few nodes are to be linked
• Communication via the Industrial Ethernet or PROFIBUS local area networks where larger numbers of programmable controllers are to be linked.