1. Programming Logic Controllers
LogixPro PLC Simulator

2. Relay Logic in Text (use courier font)
|---[ ] ( )--|
| sw mot0 |
|---[/] (L)--|
| pb mot1 |
|---[ ] (U)--|
| pb mot1 |
|-+-[ ] ( )--|
| | | | |
| +-[ ] ( )--|

3. I/O Simulator

4. Door Simulator

5. Door Sim Ex1

6. Door Sim Ex2

7. Door Sim Ex3

8. Door Sim Ex4
Example Fail

9. Door Sim Ex4

10. Door Sim Ex4
Another Solution

11. Silo Sim Ex1?

12. Silo Sim Ex2

13. Silo Sim Ex3