How to get separate return path for multiple output Transformer

Thread Starter


Joined Jan 23, 2017
Hi Guys
My power supply spec is as follows,
Input = 180 v- 440 v
Out 1(main): 5 V ,10 A
Out 2(main):12 V,1 A
Out 3: 5 V,1 A

For out 1 and 2 i need same ground and out 3 i need separate ground.
I tried in PI Expert but i m getting common return path for all the outputs as shown in attachment.
Please suggest me .



Joined Sep 9, 2010
So this is a problem in simulation? That's probably because the voltage is undefined if not referenced to ground. You could try adding a 1MΩ resistor to ground to help the simulation figure where to reference the floating voltage.


Joined Aug 21, 2008
It looks like you are off to a good srart,

Are you unable to make the winding for output #3 an isolated winding just like the winding that connects to pins 4 and 5?

If that is the problem, why is that not possible?