Reversing the rotation of a 3-phase motor how?

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sedge

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I have a 3-phase motor wired in Delta running from a 230 volt single phase to 230volt 3-phase inverter.

It runs clockwise but I want it to run anti-clockwise.
I read that to reverse the motor you swap two wires!

Which two out three U, V and W?
I think it is U and V but I am not sure.

Ken
 
Thanks.
Just wanted to be sure and not do any damage.
Ken
 
If the source power is true three phase, then swapping any two wires will reverse the motor direction. However, if you are using a phase converter and the machine also powers any onboard single phase components from that three phase power source (like lights, controllers, DRO, etc), then you should only swap the two hot (non-generated) wires that pass through the phase converter. Single phase items must not use the phase converter generated wire which can produce some rather crazy voltages.
 
I have a 3-phase motor wired in Delta running from a 230 volt single phase to 230volt 3-phase inverter.

It runs clockwise but I want it to run anti-clockwise.
I read that to reverse the motor you swap two wires!

Which two out three U, V and W?
I think it is U and V but I am not sure.

Ken

As has been pointed out swap any two wires going to the motor. That is the ultimate way to reverse a 3phase motor.

However you have indicted that you are running on a 3 phase inverter. I'm assuming a VFD, in that case he drive might support electronic reversal of direction. If that is the case ideally you should wire so that the motor rotation makes sense in the drives normal mode.

In other words the spindle you are rotating should rotate counter clockwise if this is a lathe.
 
Are you using star-delta starting? If so please reverse any two cables at the isolator.

Do not reverse wires going from starter to motor. Two things can happen. Start on "star" and motor stop spinning at "delta". Start on star and very bad phase to phase short and no starter left.

I witnessed a Malaysian Fiat Car Assembly Plant power trip with a badly wired Star/Delta Starter in 1975.

Good Luck.
 
Hi
Thanks everybody for the replies.
I never thought about the settings in the inverter, it can be set for forward or reverse.
The old adage "if all else fails R.T.F.M." applies Doh!
Ken
 

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