SINAMICS S120 Drive Simulation Using SIMIT with Basic Positioner (EPos)
This application example demonstrates how a SINAMICS S120 drive can be configured and operated as a simulated system using SIMIT, enabling virtual commissioning and testing without requiring physical hardware.
The setup connects a simulated drive, PLC, and HMI to reproduce real automation behaviour in a controlled engineering environment.
Application Overview
The example shows how a real SINAMICS S120—configured as a PROFINET device and controlled by a SIMATIC S7-1500—can be reproduced in a simulation platform for testing and validation.
This allows engineers to validate motion control logic, positioning behavior, and communication before deploying to the real machine.
Simulation Concept
The simulation environment combines multiple Siemens tools:
- TIA Portal for engineering and configuration
- PLCSIM Advanced acting as a virtual S7-1500 controller
- SIMIT SP to simulate drive and plant behavior
- HMI Runtime Simulation for operator interaction
This architecture mirrors the real automation setup while remaining fully virtual.
The simulation environment combines multiple Siemens tools:
- TIA Portal for engineering and configuration
- PLCSIM Advanced acting as a virtual S7-1500 controller
- SIMIT SP to simulate drive and plant behavior
- HMI Runtime Simulation for operator interaction
Communication & Control Principle
- The SIMATIC controller operates as a PROFINET controller.
- The SINAMICS S120 behaves as a PROFINET device.
- Data exchange is performed cyclically through PROFIdrive telegrams.
Positioning commands are executed using the TO_BasicPos technology object, which controls the drive via the Basic Positioner (EPos) functionality.
Technology Used – Basic Positioner (EPos)
The Basic Positioner enables:
- Setpoint positioning of the drive axis
- Relative and absolute positioning modes
- Homing and jogging operations
- Execution of predefined traversing blocks
This functionality is controlled cyclically from the PLC user program using standard motion technology blocks.
Typical System Components
The reference setup includes:
- SIMATIC S7-1500 controller
- SINAMICS S120 drive system with CU320-2 control unit
- SIMATIC HMI panel
- STEP 7 Professional & Startdrive engineering tools
- SIMIT simulation platform
These components are reproduced virtually for simulation-based testing.
What Can Be Tested in Simulation?
Engineers can validate:
✔ Drive positioning and motion sequences
✔ PLC-drive communication via PROFIdrive telegrams
✔ Control logic using TO_BasicPos
✔ HMI interaction and diagnostics
✔ Machine behavior without energizing hardware
This approach enables safe validation before commissioning.
Engineering Workflow
Typical implementation steps include:
1️⃣ Configure SINAMICS S120 and network settings in TIA Portal.
2️⃣ Create the TO_BasicPos technology object for axis control.
3️⃣ Use PLCSIM Advanced to run the PLC program virtually.
4️⃣ Model drive behavior inside SIMIT using telegram-based simulation.
5️⃣ Operate and monitor the system through simulated HMI screens.
Typical Use Cases
This solution is ideal for:
- Risk reduction during the startup of complex drives
- Virtual commissioning of motion systems
- FAT testing before hardware delivery
- OEM machine development
- Training environments for automation engineers
Key Benefits
✔ Commission systems before hardware is available
✔ Reduce startup time and engineering risk
✔ Test motion logic safely in simulation
✔ Improve software quality through early validation
✔ Enable digital twin–style workflows
