Tony's DIY Isolation transformer

Hello to All,
i have project i thought you may find usefull, it's a 600va isolation transofrmer with 220volt pri/sec voltages. i designed and built this from recycled psu parts..but the traffo itself is made out of fresh materials.

i can not post pictures at this time as the server hosting the pics is up for maintenance!

here is the transformer data:
core = EI 1 3/4 in CL stacked to a depth of 3incher( about 15lbs)
primary/secondary coils = 320turns each of #16 AWG single formex magnet wire, copper weight about 2kgs.
bobbin = plastic pre-formed bobin for the selected core!

and here are the pictures:
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Very nice, but, it is supposed to be an ISOLATING transformer.
What is there to prevent an "interwinding short circuit"?
Nothing that I can see.

Having the primary and secondary on separated bobins would be better.

JimB

hi,
yes, having the primary and secondary on separate bibbins would have been better, in fact i would recommend that those who would like to build this traffo, use separators between primary and swcondary windings and even faraday sheilds if they wll use this on audio set-ups! however for my own personal use, i used bifilliar windings, i have used this method on all of my transformers used for power amps! i have tested the unit under load and it worked fine! the primary circuit is fused, so in the unlikely event of a short, the fuse will blow!!! tight coupling is my primary concern as this traffo will be used on my athlon64 rig to get rid of nasty shocks! and output goes to an emi/hash filter also diy'ed:

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Another cheap way to get an isolation transformer is to scrounge two *identical* transformers. These must have isolated secondary windings, do NOT use autotransformers.
Just connect the secondary of one transformer to the secondary of the other. Their primaries are now isolated by two separate bobbins.
There might be a slight derating of the output due to transformer losses.
Klaus

yes, i have done that before too!!!