本帖最后由 td456 于 2010-4-14 12:28 编辑 # a4 v A$ C$ ^8 D
Y- M v/ _. ]& p+ z. o3 cWe all know that if you want to change the rotation of a three phase AC motor. 1 U* P9 {/ |/ ]9 B( [9 E* N& S0 F: FJust swap any of the two phase leads. % @4 G. G; G3 r: m# ^6 `But for VFD application you need to do the swap after the inverter.. z( [1 H3 q( W& U# c/ Z
If you swap the leads before the inverter, it will not work.
Yes, Good point. 5 p) M) t; u% h# x# m( \5 u [
As the principal of the VFD works, bascially from AC to DC, then DC to AC. : i2 O$ e# u% X9 o % K( I. J% m* D3 w' _* ~The 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. . k8 T1 ?0 d- I2 Z( E- r6 A2 H+ f * b0 A; K& R# A" ~The only thing you can change the rotation of the motor is the output side of the VFD, NOT the input of the VFD.