reverse three phase to reverse rotation

I always try to set up a VFD/Motor system so "forward" on the machine is "forward" on the drive. While IEC and NEMA define forward on the motor, I have never paid any attention to it.

I'm more concerned that when the machine is running forward, the drive display reads forward and the control system is signaling forward. In the future, some service technician will appreciate having the system set up that way.

You do have to be careful with mechanical components as a rare few are designed to run better and lubricate better running one way over another. But, this is usually a mechanical design issue, not electrical.
 
Many many moons ago, in the days of analog drives, some drives came with a dip switch on the board that “inverted” the output rotation. It allowed the person doing the setup to change rotation on the motor while still having the drive inputs and LEDs refer to Fwd and Rev, because really, it’s all relative. That concept seems to have disappeared.
 
I always try to set up a VFD/Motor system so "forward" on the machine is "forward" on the drive. While IEC and NEMA define forward on the motor, I have never paid any attention to it.


Exactly...we only reversed our conveyors under emergency conditions and for only a few inches because all the equipment that was mechanically interlocked to other equipment on the production line. There would never be any question which direction the conveyor would run in the forward command.

Depending on the mounting of the motor our conveyors could have also supported the IEC & NEMA standards.
 
Exactly...we only reversed our conveyors under emergency conditions and for only a few inches because all the equipment that was mechanically interlocked to other equipment on the production line. There would never be any question which direction the conveyor would run in the forward command.

Depending on the mounting of the motor our conveyors could have also supported the IEC & NEMA standards.

agreed. this is how I am used to doing
 
I always try to make it so that the FWD drive rotation is "normal" direction. I don't want someone to see "REV" on the drive and assume things are running in reverse.
 
Almost all the drives I work on have an "invert rotation" parameter.

I almost pulled my hair out looking for one on the PowerFlex 70EC.

But no, the direction is fixed:

A before B on the encoder = Forward = counterclockwise viewed from the tail end.
 
Is it possible to wire correct during drawing? Swapping phases on 100's of motors would be nice to avoid. Is phase naming that standardised between different motors and brands of vfc?
 
I'll connect the wires so as to make the motor turn in the direction I want it to go at the default direction parameter setting.

I always did the same and installed hundreds of drives, no issues.
A few weeks ago, I experienced a "strange one"
A standard 3 phase motor, with an Invertek Vsd. Connected up and switched ON, direction fine, all happy. Switched OFF and before I left, I switched ON again and could have sworn, it went in the opposite direction.
Switched ON/OFF about 50 times and on every start up, it would hesitate and then pick which ever direction it felt like. It usually went clockwise, but about 10% of the time it went anti clockwise.
I rang the Invertek rep. and he said, I had forgotten to do an "autotune".
I proceeded to do an "autotune" and perfect after that.
I was lucky that direction was not critical with that particular machine, but shows you can't bee too careful.
 

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