projects on plc
Hello ayyub,
Do you have to make a "proof of concept" type project ?
If so, you could think in boiler protection for power generation or petrochemical plants.
It can be relatively easy for single burner boilers, and more involved if you consider multiple burners, operative restrictions such as non intrusive manteniance, etc.
By standards, you must not do regulatory control and boiler safety control in the same PLC, unless you use an adequate (and certified) PLC.
To understand some the interlocks to be considered, you can refer to NFPA 85 and NFPA 86.
If you have to do a "real life" proyect you have also study IEC 61508 and 61511.
Hope this helps.
Best regards!