richardzhng 发表于 2011-12-12 19:38 : ?1 L2 m: L/ }( Z; A( \% e# P6 k
are you sure it is three phases and one neutral, not three phases and a ground?
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"are you sure it is three phases and one neutral, not three phases and a ground?" / X% t/ s) s e' s! n: b6 L5 n ' n2 U( ^" o- O( ^+ s4 y1 P r, x* ~/ Z1 s7 a! y3 l( g% l; jI am sure . Would you gave me some advice? thanks!