Comprehensive Analysis and Application Guide for SIEMENS S7-PLCSIM Advanced Simulation Software

Create simulation instance: In the control panel, name the instance, select the PLC family (such as S7-1500), and start the instance.

Download project: In the download dialog box of TIA Portal, select the appropriate PG/PC interface (such as "PLCSIM" or "Siemens PLCSIM Virtual Ethernet Adapter") according to the communication mode, and download the hardware configuration and user program to the virtual PLC.

Operation and monitoring: Switching the virtual PLC to RUN mode allows for program debugging and diagnosis through TIA Portal's monitoring table, forced variables, and other functions, or through the control panel.

Advanced simulation function

Virtual time response: This is a unique feature of S7-PLCSIM Advanced. Users can enable 'virtual time' for simulation instances and accelerate or slow down the virtual clock by scaling factors (0.1 to 1000). This only affects time-based components (such as the call interval of loop OB) and does not affect code execution speed. This feature is very useful for testing time related logic or accelerating long-term process simulations.

ODK Function Simulation: Supports simulating custom function libraries for CPUs with Open Development Kit functionality (such as CPU 1518-4 PN/DP ODK). These function libraries written in C++run in separate "ODK client" Windows processes and are executed synchronously with STEP 7 user programs.

Motion Control Simulation: Supports basic motion control function simulation of S7-1500T technology CPU and SIMATIC Drive Controller. The logic of the technical object is simulated within the PLC, while the actual axis dynamics need to be simulated by connecting external simulation software through an API. Attention should be paid to the overflow detection of OB91 (MC Servo).

Redundant system simulation: Supports simulation of S7-1500R/H redundant CPUs, but is limited to the "RUN Solo" system state, which means a single CPU runs independently and cannot simulate the redundant synchronization and switching process between two CPUs.

Key Limitations and Precautions

Despite its powerful functionality, there are still differences between simulated environments and real hardware, and engineers must be aware of the following key limitations:

Non complete determinism: The simulation runs on a Windows system, and the precise timing of scanning cycles and actions may be affected by other processes on the PC, which may not be completely consistent with the behavior of physical hardware.

Hardware and bus limitations: Do not simulate fieldbus systems (such as PROFINET IO, PROFIBUS DP), real I/O modules, communication modules/processors, and CPU body I/O (only accessed as process images). I-Device functionality, copy protection, configuration control, and other functions are also not supported.

Some features have limited support: simulation of diagnostic buffer entries, some online diagnostic functions (such as firmware updates), and certain instructions (such as DP_TOPOL, T_CONFIG under Softbus) have limitations or are not supported.

Communication service limitation: When using Softbus, the TUSEND/TURCV (UDP) command will report an error and needs to switch to TCP/IP mode. MODBUS communication has specific requirements for library versions.

Security considerations: Simulation communication does not provide authentication and authorization protection by default. When communicating across computers, it is strongly recommended to use a closed simulation network that is isolated from the production network.