本帖最后由 td456 于 2010-4-14 12:28 编辑 ; D5 G- B3 ^$ C7 ~+ p5 T
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We all know that if you want to change the rotation of a three phase AC motor.# q8 _* v4 T2 E& }
Just swap any of the two phase leads. t' A4 a T/ P. uBut for VFD application you need to do the swap after the inverter./ Z6 ^2 z4 Z- j& {& M0 P: X% U! k
If you swap the leads before the inverter, it will not work.
Yes, Good point.; e* z7 h4 k6 @; a# X: ^3 ]
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As the principal of the VFD works, bascially from AC to DC, then DC to AC. " P3 B* {8 G9 G/ v4 D0 D" c8 p4 j5 o0 g( Y
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. 7 @! i: P$ j# E5 q& L# y! g! R& j) e9 E/ |
The only thing you can change the rotation of the motor is the output side of the VFD, NOT the input of the VFD.