I am doubtful either use Modbus or Canopen; both have advantages
What are you looking to use them for?
As main controller for the elevator; the PLC should be more reliable than customized electronic boards.
If you want to move data then you should use modbus but if you want to control I/O then Canopen
I need both; any way Modbus is used on PLC to control I/O.
Nouman Khalid can you do both?