Verifying direction of rotation. 2

[Shingai]

Hi guys.what is the best way to check if a motor is rotating in the right direction after installation or repairs on supply cable,without having to uncouple the motor.in particular situations where motor is driving equipment which is sensitive to direction change

 

[jraef]

If you can ensure that the original connections are the same, you will not need to. But you cannot guarantee rotation direction without testing.

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[ScottyUK]

If you know the phase rotation sequence prior to the repairs taking place then you could make a comparative rotation check with the motor disconnected.

 

[eeprom]

You can use a phase rotation meter. You hook up the motor leads to one side of the meter, and the line power to the other side. The you would have to physically spin the motor (not very fast, just by hand). The meter will tell you if the motor direction matches the line phasing. But you will have to be able to turn the motor, so you might have to uncouple it anyway.

 

[Kapil1982]

it's simple, standing at NDE the motor should rotate CW

 

[ScottyUK]

Kapil,

How can that possibly be a sensible or simple solution in circumstances where, to quote the OP, "the motor is driving equipment which is sensitive to direction change "?

As many of my teachers used to say to me, "Read the question before answering it."

 

[crthompson]

I agree with eeprom...

 

[ScottyUK]

eeprom,

Can you expand a little on how to connect the rotation meter? Do you mean connect power to U1 / V1 / W1 and connect the meter to U2 / V2 / W2? I am trying to understand how it will determine correct or incorrect rotation of the shaft from such a connection.

.

 

[Skogsgurra]

We have discussed this several times. One thread that might be helpful is this: thread237-265331

Gunnar Englund

http://www.gke.org

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