I was shown how to use two transformers to step up voltage and I am curious as to how it works. The low side of the transformers were connected to 120v and the high side was connected to a load at 240v. What amazed me was that the low sides connected in series could be connected to the 120v wall outlet(Hot Leg and Neutral) with no load on that side and not be a short circuit. Is this right? Was it only working because the high side was connected to a load? Would it not work or be dangerous if there was no load connected to the high side? Open voltage? Are the coils enough resistance to prevent a short or is it that until a load is on the high side, there's no draw?