本帖最后由 td456 于 2010-4-14 12:28 编辑 6 j$ @; P$ h ~& r% |. e' T% `7 `; s4 k, Z2 n" A
We all know that if you want to change the rotation of a three phase AC motor." ^1 r+ v. g1 @) u9 h3 h* R
Just swap any of the two phase leads.2 O6 S+ N* ~3 i& s" u
But for VFD application you need to do the swap after the inverter. 1 z+ ^% m* Y _& E/ _2 zIf you swap the leads before the inverter, it will not work.
3 Y4 z+ {4 ~( O7 \. o \' b; ]As the principal of the VFD works, bascially from AC to DC, then DC to AC. 2 E8 y3 D9 [ ?6 Y8 P& D9 t p / M- M5 _% P& JThe phase rotation of the output of the VFD connecting to the motor is based on the sequence "open" or "close" controlled by the inverter pre-set inside; any changes to the phase rotation of the feeder will not affect the DC rotation, as DC is NO phase at all. % G) G! b: a/ p! B 0 J: _1 S3 m! w" t% GThe only thing you can change the rotation of the motor is the output side of the VFD, NOT the input of the VFD.