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Transformers connected in reverse Answered


can a transformer connected in reverse.
if 230v to 12v transformer is connected in reverse,. will it generate around 230v

Just some silly doubt.
Actually i was trying to find a step up transformer.. which converts 6v to 24v. what exactly its called.


Can A Microwave Oven Transformer Be Connected To 120 VAC Backwards?

Like Connecting 120 VAC Into The 2.1 KVAC Side And Get A Output Of Around 12 VAC?

Hi! :-)

Take a look at this:


Hope this helps you. I`m going to order one soon and I can post a new note when I`ve got it and tried it.
- R :-)

You can do this, but be careful about the input current - you might "fry" something depending.


.  There is no forward/reverse to a transformer. It works just as well one way as the other. As gmoon points out power (E*I) on both sides will be the same.


8 years ago

Yes, you can connect a transformer in reverse. And that's 12V AC, of course.

However, the voltage : current relationship will be reversed. A load on a 12V secondary will draw less amperage on the 230V primary.

But if it's step-up, it's the opposite: A load on the 230 secondary will draw MORE amperage on the 12V primary.

But the 230V winding was designed only to handle the amperage needed to supply the power rating of the original (12V) secondary. Just keep that in mind, and you'll be OK.

Search some of the ibles on MOT microwave oven transformers used as power sources for homemade welders.  There might be clues in there.  Good luck.