can i increase the isolation level by adding two device in series

[shaswat]

I want to know that during designing can I enhance the rated voltage of a device by adding two device having same rated voltage in series?
I mean that if a device has operating voltage of 440 v and I want to operate that design on 800 v then by adding that two device in series would help to operate my design at 800v ??

 

[Mr.Cool]

in general yes. assuming your two systems have same impedance, then the voltage drop across each will be 1/2 for same series current. this is ohms law.

more specifically, there is a lot more to consider, the least of which is if your system will still operate properly if it is floating (only one of the two systems will be referenced to ground!).