Sub Panel

[pbeasley]

I don't remember all the details, but we had problems in our apartment while living in Hong Kong. There was some kind of shunt in the apartment main panel. When we lost a leg on the main feed, it tripped the whole panel. To this day, I don't know the how or the why of it, only what was explained to me and what they did to fix it.

the safe-t-cut panel may be similar in operation and may require all 3 phases to function.

 

[PetrosA]

If your system is similar to what I know from Europe, you'll have three phases @ 230V to neutral, 380V between phases. In Poland, a typical single family dwelling would be fed with a 25A 3? service, with a GFI MAIN protecting the entire installation. That gives roughly the 14.4 kW rating. Anything larger would require special approval as a commercial service.

That said, My first question to you is this: Is that Square D panel accepted for use in Thailand? If you have a three phase service, it should be continued to any sub panels you install for load balancing. The other option I've seen in Europe is a split MAIN panel (I think they're 100 A though.) where you can feed multiple 3? busses, each protected by it's own 3? MAIN GFI breaker ("busses" in Europe are copper strips installed one at a time from load lugs in the breaker). It allows you to separate appliances from lighting so the entire house or apartment doesn't shut down on a ground fault. Look into what's available locally to do what you need, and talk to your electrician so that he understands what it is you want to achieve.