3 Phase Motor

It will spin the other way!

thank you.........

Tcmtech is right.

Before linking a motor to its mechanical load, it's always a good idea to check if its phases are in a proper sequence.

Connect the motor feeds and give the motor a short burst of electricity.

If it spins the right way, disconnect the power and connect the motor to its load.

If it spins the wrong way, cut the power, interchange any two power-feed connections, and connect the motor to its load. Interchanging any two feeds will make the motor spin the right way.

Cheers!

Dread Zontar

Reshuffle all three wires - direction will remain unchanged.

Interchange any two wires-direction will change.

^{"hi to all,}

^{what will to a 3ph motor if its phase has been changed?}

^{ex: RYB(connection in source) is connected to BYR(connection in motor)"}

Reading this more carefully (or more specifically if you like), TECHNICALLY the motor phasing and source phasing are completely irrelevant and the direction of rotation is completely subjective. The FIST TIME you hook up a motor, it just turns the way it turns. You cannot, with 100% certainty, predict which direction it will spin the very first time. So saying that "it will spin the opposite direction" is a relative statement in the context of a relationship to supply and connection. Opposite of what?

Now IF (and you didn't say) the motor HAD BEEN spinning in one direction AND THEN you change the phasing, it will spin in the opposite direction.

Yes and no, concerning phasing/rotation subjectivity.

But instead of figuring out what is the phase sequence for a power feed (whether by documentation or by using a phase sequence detector) and the coil sequence a motor by reading its manual, which is time-consuming and subject to error, it's best to just connect the power feed and give 'jog' teh motor (give a short power burst) to see which way it turns.

A given phase sequence from the power feed and the power feed's being connected to a motor in a given way will always make the motor turn the same way. And for a given power-feed phase sequence, half of the possible connection-combinations will make a motor turn clockwise, and the other half will make it turn counter-clockwise.

It's just faster and surer to just connect a power feed and then see which way a motor turns.

I agree with DreadZontar, the IEC specification for motors actually describes that for a certain phase rotation the motor will in a clockwise direction. So if the manufacturer complies to the specification, his motor will always rotate in the "same" direction (dependant on the phase rotation off course)

change in direction of rotation