Is this galvanic isolation?
You'll have galvanic separation between the mains and AC motors on one side, and the 24V/5V on the other side, because of the mains transformer. You also may have separation between 24V DC and 5V DC, but most regulators don't provide that. You'll need an isolated DC/DC converter, where the transformer takes care of the isolation.
If you have that you have 3 mutually isolated parts:  


Mains and the AC motors  
24V supply and DC motors  
control part


If you don't the 24V motors aren't separated from the control part, despite the optocouplers.