richardzhng 发表于 2011-12-12 19:38 " I- i4 x0 w% w# X. Q
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?" 7 L6 Q: q6 L: ^( l. i9 H1 H/ @* t* L) n% x8 W( } { m
4 o" G# m; F3 q) p( {3 Z JI am sure . Would you gave me some advice? thanks!