Home produced 700VA isolation transformer

This a quick post regarding homemade 300V - 2.3A isolation transformer. This transformer is a part of my ongoing 300V AC/DC variable power supply project and it’s boxed as a separate unit because of its heavy weight and size.

700VA isolation transformer with enclosure

All the parameters of this transformer are calculated using small Python script which I was written sometimes ago. This script support for step-up, step-down or 1:1 power transformer windings and it can execute on any platform where Python 2.7 (or newer version) is supported.

In isolation transformers separation between primary and secondary windings is an important factor. In this transformer I use multiple layers of 3M Scotch Electrical Insulation tape as primary and secondary winding separator. Standard 50mm PVC electrical insulation tape is used to cover secondary winding of this transformer.

Improper connections or construction of this transformer may leads to fire or lethal electrical shock. Because of that reason, make sure to take all the necessary precautions while constructing, testing or using this transformer. Do not try this project if you don’t know what you are doing!

Comments

Anonymous said…

Looks like factory made. I have made some SMPS transformers, but nothing with that much heft.

Does the python script assume the line frequency? I didn't see an input for that.

March 26, 2014 at 6:49 PM

Dilshan Jayakody said…

Line frequency you need to specify at the run-time.

In 4th question it ask "Primary Input Frequency (Hz): ".

The main assumption I made in this script is magnetizing force value and which is set to 60,000.

March 26, 2014 at 9:29 PM

Unknown said…

Hi very nice post. Very well built Isolation Transformer.
Thanks for sharing this blog.

March 28, 2014 at 5:48 PM

Unknown said…

Nice post and thanks for sharing this article.We also manufacturers of Control TransformersControl Transformers Manufacturers

May 28, 2014 at 6:39 PM

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