Mini Guide: TIA Portal Key Programming Concepts Explained

This quick-reference guide explains the essential elements you’ll use when programming in TIA Portal.

PLC Tag

A PLC tag is a variable name assigned to a physical or logical input/output or internal memory in the PLC. It links your logic to actual hardware or simulation.

• Example: "PICK_Stopper_EXTENDED" – controls an actuator to extend a stopper.

CASE Structure

A CASE structure is a step-based control logic used to organise sequences and machine states.

🔹 Example:

CASE #Step OF

  0: // Initialization

  10: // Wait for sensor

  20: // Move actuator

END_CASE;

Great for sequencing processes such as pick and place or sorting.

IF Statements

Used to check conditions in logic. If the condition is true, the block of code is executed.

• Example:

IF "PICK_SENSOR_Stopper_WORKPIECE" THEN

  "PICK_Gripper_GRIP" := TRUE;

END_IF;

Variables

Named data points used to store sensor values, actuator states, timers, counters, or control flags. You declare them in data blocks or locally in function blocks.

Timers

Used to introduce delays or check elapsed time.

• Timer Type: TON (Timer On Delay)

•  Used With:

#DelayTimer(IN := TRUE,
    PT := T#1s);

IF #DelayTimer.Q (timer finishes) THEN (do action)...

RESET_TIMER(timer_name); - resets timer

Delays

Delays are managed using timers. Timers help ensure reliable sequencing or physical actuation before the next step begins.

• Use for: suction grip delay, actuator travel time, sensor debounce.

Counters

Used to count events, like number of workpieces or cycles. You can implement manual counters with INT variables.

• Example:

IF "Sensor_Part_Entered" THEN

  #WorkpieceCounter := #WorkpieceCounter + 1;

END_IF;

Lists

TIA Portal does not support traditional arrays in HMI/PLC, as is the case in other languages. However, you can simulate list behaviour using structured data types (UDTs) or arrays in data blocks.

• Use structures like:

Slide1.Red, Slide1.Black, Slide1.Silver

HMI (Human-Machine Interface)

Used to interact with the system. In TIA Portal, you can design HMI screens to:

• Input orders (e.g., number of red/black pieces)

• Show current counters

• Display station status

• Activate manual mode

HMI Tags

HMI tags are variables explicitly used in the HMI interface. You link HMI tags to PLC tags for two-way communication.

• Example: An HMI input field updates Slide1.Red in PLC.

Function Block (FB)

A modular block of logic with memory (uses a Data Block). Each station should have its own FB for clean, organised programming.

• Example: FB_SortingStation, FB_DistributionStation

Data Block (DB)

Stores all the variables and state information for a function block. Can be shared or instance-specific.

• Automatically created when you insert a function block.

PLCSIM Advanced (PLC Simulation Advanced)

PLCSIM Advanced is Siemens’ professional tool for simulating virtual PLCs, such as S7-1500 or ET 200SP CPUs, enabling complete testing without hardware.

• Key Features:

  • Simulates logic, timers, counters, and signals.

  • Works with TIA Portal + Siemens NX MCD (Digital Twin).

  • Supports multiple virtual CPUs.

  • Supports network communication and HMI interaction.
    
    

Used to test digital twin models, monitor signal flow, and run real-time simulations with NX MCD.