The house currently has a 3/4 inch conduit to feed the main wires coming from the power company to the breaker box. This is very much inadequate. I plan to upgrade to a much bigger breaker box. My question is what size wire should i use from the meter to the breaker box. There is no NEC or any kind of regulation here and SE wire doesnt exist here so ill just run separate wires through a new conduit.
For a 200A residential service in the US or Cananda typical would be 4/0-4/0-2/0AL or 2/0-2/0-1/0CU conductors. Either combination would normally be run in 2" conduit.
This is only scratching the surface of what you need to know to do this project. Are you aware and knowledgeable of all the other requirements/codes/etc???