SIMATIC S7-GRAPH
Programming sequence controls
SIMATIC S7-GRAPH is based on the STEP 7 programming software. It is
used for describing procedures with alternative or parallel step sequences.
The procedures are configured and programmed clearly and quickly in a
standardized method of representation (to IEC 61131-3, DIN EN 61131). The
process is described graphically, and divided into individual steps with an
easily comprehensible scope of functions. |

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Actions can be defined for the steps, and their execution controlled.
Transitions control the conditions required for the next step. Interlock and
monitoring conditions are defined for each step.
Additional benefits over LAD, FBD, and STL:
- LAD, FBD and STL focus on logic control. S7-GRAPH places more importance
on the process sequence.
- Clear graphical representation of the process using sequencers, providing
easy maintenance and modification/ adaptation of the programs if required.
- Process error troubleshooting with integrated diagnostics functions;
expensive downtimes during production are minimized.
Example of an application
A typical example of a sequential operation is a drilling procedure with the
following steps:
- Drilling machine ready
- Clamp workpiece
- Start drill motor, optionally coolant pump on
- Lower drill
- Raise drill
- Coolant pump off, motor off
- Open the clamp
For programming compliant with IEC 61131-3 and PLCopen Base Level, the
following functions are available:
Basic functions
- Flexible sequencer structure:
- Simultaneous and alternative branches,
- jumps within the sequencers,
- step enabling and disabling.
- Selective processing of steps.
The processing time of a sequencer is thus independent of the number of steps.
- Synchronizing automatic and manual operation
The process is not synchronous anymore when it was placed into a different
state manually.
S7-GRAPH supports the locating of synchronization points for restarting
automatic operation. To do so, the relevant steps are marked. Step-enabling
conditions or interlocks can be defined as criteria.
Licensing
S7-GRAPH is part of the STEP 7 Professional Software package yet also available
separately. Customers that already use STEP 7 can change to STEP 7 Professional
by purchasing a POWERPACK. A valid STEP 7 license is needed for this upgrade.
Software Update Service is offered for the STEP 7 Professional package as well.
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