palletizer

Description
This SCL function block FB_PalettierStation controls a simulation of a "fully automatic palletizing station" with pallet empty check, product detection, gripper control, and layer handling. It runs in the Siemens TIA Portal.

Note: All modules are designed exclusively as a learning and optimization basis and are not approved for live operation. System modules, in particular, must be finally tested and commissioned by qualified personnel before productive use.

How it works

1. Security check
   – Stop = TRUE or PaletteEmpty = TRUE → Conveyor belt, gripper and lift off, alarm & error on, step = 0, status text = "Pallet missing or emergency stop active", RETURN

2. Cycle start
   – Start edge detected when ProductDetected = TRUE and Error = FALSE → Step → 0

3. Step 0
   – Conveyor belt on until start edge = TRUE → step → 1

4. Step 1
   – Wait for GripperReady = TRUE → GripperActive = TRUE (Pick up product) → Step → 2

5. Step 2
   – PalettePositionOK = TRUE → GripperActive = FALSE (drop off) → Step → 3

6. Step 3
   – ZaehlerProducts++
   – CounterProducts ≥ TargetQuantity → CounterLayers++, LiftRequest = TRUE
   – Step → 4

7. Step 4
   – CounterLayers ≥ LayersPerPalette → PaletteFull = TRUE, Error & Alarm on, StatusText = "Pallet full - please change", Step → 0
   – Otherwise → Step → 5

8. Step 5
   – Conveyor belt on
   – LiftRequest = TRUE → pallet lift on, StatusText = “Lift moves to next layer”
   – LiftRequest = FALSE → StatusText = “Next product ready”
   – Step → 0

Technical details
• Inputs: Stop, PalletEmpty, Start, ProductDetected, GripperReady, PalletPositionOK, Acknowledge, TargetQuantity (INT), LayersPerPallet (INT)
• Outputs: Conveyor Belt, Gripper Active, Pallet Lift, Alarm, Error, Pallet Full, Lift Request, Status Text (STRING)
• Internal variables: Step (INT), StartEdge (BOOL), CounterProducts (INT), CounterPositions (INT)
• Flow control: CASE structure on “step” with RETURN in case of safety errors
• Acknowledgement: Acknowledge = TRUE → Alarm, Error, PalletFull, LiftRequest = FALSE, StatusText = “Error acknowledged – ready”

Possible applications
• Fully automatic palletizing systems in logistics and production
• Retrofit of existing conveyor systems for flexible layer structures
• Training and demonstration systems to illustrate complex step sequences

compatibility
Siemens S7-1200 & S7-1500; TIA Portal V13 and higher (V16+ recommended for HMI & PLCSIM)

Scope of delivery
• .scl file with input/output declarations, internal variables and CASE logic
• Header comment with author, website, email as well as information on target quantity and layers per pallet
• Download link immediately after purchase

Support
Adjustment of meter parameters, integration of additional sensors or HMI layouts on request via shop message or email.