It will work but it is generally it is not a good idea as if you lose power to your plc you lose alarming and visibility of your process. I like to ensure my plc always has power so I know what is going.
Ideally all your devices should go to failsafe position on loss of signal but this is not always the case depending on your setup you may have motors that keep running or valves that stick open.
As long as you know the risk and don't let it linger it can get you through