Simatic S5 PLC is automation system based programmable logic controllers (PLCs). This product is manufactured by Siemens. This automation system is widely used in machinery and equipment control systems. Actually Simatic S5 PLC product is obsoleted. This product has been replaced by a new generation of Simatic S7 PLC.
However Simatic S5 PLC has many installed in most factories and companies around the world. So that the product of S5 PLC is still available to support these industries.
Products from S5 PLC are available in various chassis styles such as, 90U, 95U, 101U, 100U, 115U, 135U, and 155U. The increasing numbers of this model is more expensive.
The S5 product line usually is programming with PC-based software programming tool called Step 5. Step 5 is used for programming, testing, commissioning and documentation for the program Step 5.
Original version of this Step 5 ran on CPM operating system version. The next version ran on MS-DOS. And then version of Windows XP-based. And the final Step 5 version 7.2.
Siemens also took a proprietary state logic programming, called Graph 5. Graph5 is a sequential programming language intended to be used on machines that operate through a series of discrete steps.
Step5 allows to create a simple operations AND / OR program up to complex subroutines. Step5 structure offers a number of facilities:
a. Block Technique, a linear sequence of operations which is divided into sections and packed into the individual block.
b. Segments, within the block, fine-structuring allows for programming subtask in the segment.
c. Comments - Both a complete program as well as individual blocks or segments and the individual statements can be directly provided with comments.
Step5 program can be represented in 3 different ways:
1. Statement List (STL), the program consists of the command mnemonic code which is executed by the PLC.
2. Ladder diagram (LAD), automation system which is represented by a row of charts and symbol circuit diagram.
3. Function Block Diagram (FBD), graphical representation of the automation tasks with symbols to DIN 40700 / DIN 40,719.
There are 5 block diagram available in Step5:
1. Organization blocks (OB) - for managing the control program.
2. Programming blocks (PB) - contain the control program structured according to functional or process-oriented characteristics.
3. Sequence blocks (SB) - for programming sequential controls.
4. Function blocks (FB) - contain frequently occurring and particularly complex parts program.
5. Data blocks (DB) - for storing data required for processing the control program.
Step5 has three distinct operations, namely:
a. Basic operations, including the linking, saving, loading & transferring, counting, Comparing, arithmetic operations, module operations.
b. Supplementary Operating and complex functions, including the substitution statements, testing functions, word-by-word logic operations, decrement / increment and jump functions.
c. System operations, direct access to operating systems.