本帖最后由 td456 于 2010-4-14 12:28 编辑 1 v% F' R/ M$ o* i1 h+ U . e5 N" A0 X4 LWe all know that if you want to change the rotation of a three phase AC motor.& g/ \4 m/ z: s9 T! W# g3 U
Just swap any of the two phase leads. # j+ J. t- k/ a% OBut for VFD application you need to do the swap after the inverter. $ i& `3 ^8 b/ x3 d+ r; V5 qIf you swap the leads before the inverter, it will not work.
Yes, Good point.& M. w2 i' B! n- v
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As the principal of the VFD works, bascially from AC to DC, then DC to AC. ; Z9 f( S8 n+ V
. a- F# w g" bThe 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. 8 [: h* ?+ y j" C. F - k' c T$ j) W' \% w5 p9 Y7 N/ LThe only thing you can change the rotation of the motor is the output side of the VFD, NOT the input of the VFD.