Autotransformers in solar energy applications

[Alex Towers]

Regarding your original question, you don't really have many options.

Sorry for not indicating, the growing popularity of these auto-transformers is mainly attached to off grid applications. The EU version of modern off grid inverters (220vac single phase) are way very cheaper than their US split phase counterparts, thus many DIY guys are posting videos on how use an autotransformer to get 120/240 split phase out from a 220vac line as a cheap solution. A safety issue raised as these european models has it neutral bonded to ground adding to that, auto transformers are not self isolated as a general purpose transformer is.

 

[berkeman]

Thread closed temporarily for safety review...

 

[berkeman]

Sorry for not indicating, the growing popularity of these auto-transformers is mainly attached to off grid applications. The EU version of modern off grid inverters (220vac single phase) are way very cheaper than their US split phase counterparts, thus many DIY guys are posting videos on how use an autotransformer to get 120/240 split phase out from a 220vac line as a cheap solution. A safety issue raised as these european models has it neutral bonded to ground adding to that, auto transformers are not self isolated as a general purpose transformer is.

I think we've covered the technical and regulatory issues pretty well, and since the thread may veer off again into discussions of not-very-safe practices, it's best if the thread remains closed now.

Thanks to all for the very helpful replies.