Hi everyone,
I am having trouble understanding following schematic. How third phase is utilised here. TIA

 

You picture is too blurry to read.

 

Blurry is the least of the problems with the drawing. It is not a normal circuit schematic drawing at all. Thus the symbols have much different meanings, and while it may be clear to some, it is hidden from me.

 

From the terminology and components, it would appear to be some form of HF Inductive heater.