Hi, I am working on inverter circuit....i am going use a circuit from google...But my doubt is about the transformer i am going to use...I have 220 v to 12 transformer....can i use it as step-up by connecting in reverse ..?and one of my friend said that,there may be problems ,when any load is connected although it gives 230v output......What is the reason for this...?I i have 100 watts load how to choose the transformer?