Level crossing with barriers & lights

You are looking for an SCL function block for an automatic level crossing barrier control system with emergency stop protection, flashing light, blocking signal, and multi-stage status logic. It can be run directly 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. Emergency stop activated → all outputs off, flashing light off, alarm, RETURN
2. Step 0: Barrier open, waiting for “Train_Entry”
3. At train_entry → flashing light on, blocking signal active, move barrier_CLOSE (step 1)
4. Limit switch "CLOSED" reached → Stop, change to step 2 (waiting for train exit)
5. At train_exit → barrier_OPEN (step 3)
6. Limit switch “OPEN” reached → flashing light & locking signal off, back to step 0
   • Invalid step → fallback to open basic position

Technical details
• Inputs: Emergency stop, train entry, train exit, limit switch “CLOSED”/“OPEN”
• Outputs: Barrier_OPEN, Barrier_CLOSE, Flashing light, Signal_Blocked, Alarm
• CASE structure with integer variable step (0–3 + fallback)
• RETURN in case of security breach immediately stops all actuators

Possible applications
• Automated level crossings in industry & logistics
• Model railway training, retrofitting in existing systems
• Trade fair or laboratory demos for safe PLC sequence control

compatibility
• Siemens S7-1200 & S7-1500
• TIA Portal V13 or higher; recommended V16+ for HMI & PLCSIM

Scope of delivery
• .scl file with inputs/outputs, variables, CASE structure & fallback
• Immediate download link after purchase

Support
I can support you with signal adjustments, additional security features, diagnostic logging, or HMI integration. Get in touch via shop message or email.