adccommunitymod (AutomationDirect) asked a question.
Why CW and CCW stays by switching input phases ?
Created Date: March 26,2007
Created By: Eltec
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People, Im trying to understand why a drive stays turning Clockwise and counterclockwise , even wenn input phases are switched ? Please help me on this one ? Kind regards, Ben / Belgium
Created Date: March 26,2007
Created by: Tom Jenkins
Well, the VFD converts the AC input to DC, and then back to AC again. Since DC current is, by definition, in one direction only, the orientation of the AC phases doesn't matter - the DC is still DC.
The inverter section that converts the DC back to three phase AC is based on the IGBTs etc. that operate from the power drawn off the DC bus. Therefore, they will always have the same phase orientation.
If your motor is rotating the wrong direction you need to swap two leads on the output side of the drive, either at the motor or the output leads in the VFD.
Created Date: March 26,2007
Created by: Eltec
People,
Im trying to understand why a drive stays turning Clockwise and counterclockwise , even wenn input phases are switched ?
Please help me on this one ?
Kind regards,
Ben / Belgium