本帖最后由 td456 于 2010-4-14 12:28 编辑 . @0 R8 N) B2 Q1 M, q( B. R+ c
; c1 s3 y! S# {$ G5 nWe all know that if you want to change the rotation of a three phase AC motor. / e3 E. t: }; c7 O' TJust swap any of the two phase leads. , W4 L% t5 s# P3 x% ]! Z+ FBut for VFD application you need to do the swap after the inverter., M$ f7 F9 A; f6 ]
If you swap the leads before the inverter, it will not work.
! `1 O+ W$ D9 F* y! K( ]7 d2 [4 jAs the principal of the VFD works, bascially from AC to DC, then DC to AC. ( `5 q6 k; y7 k$ ^( Z: @2 w % x7 o' O1 {4 B/ V' nThe 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.: d; b! |2 z* I9 t. F' a- ]9 p
( N# F+ h0 S: X) I% B5 NThe only thing you can change the rotation of the motor is the output side of the VFD, NOT the input of the VFD.