A Tip on changing 3 phase AC motor rotation

td456

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$ d- H& q# e- K% `3 cWe all know that if you want to change the rotation of a three  phase AC motor.
" M* ?( k6 a0 T6 FJust swap any of the two phase leads.
But for VFD application you need to do the swap after the inverter.
9 m2 T( b1 p6 WIf you swap the leads before the inverter, it will not work.

nw123

go go go

MrElectrician

Yes, Good point.
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As the principal of the VFD works, bascially from AC to DC, then DC to AC.
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# z) [, T0 v" n0 C6 j# gThe 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.
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The only thing you can change the rotation of the motor is the output side of the VFD, NOT the input of the VFD.

jiodiangong

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