×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

6 lead 2 speed motor

6 lead 2 speed motor

6 lead 2 speed motor

(OP)
help !!!!!!!!!!!!!
troubleshooting 6 lead 2 speed motor 3 phase 480 volt.
I am not familiar with this motor and I would like to know if I have done the troubleshooting correctly. It is a 3 starter setup, high low speed, checked the all contactors, pulling all the wire off, and checked continuity between the starter and the overloads.  Everything was good.
I checked the voltage at the pecker head and had good voltage.  I also ohmed motor to case. It showed no ground.  Checked ohmes on motor leads and it came out pretty close ranges between all leads.  After all of this the motor is still not working properly.  Low speed works fine.  At high speeds it sounds like it is single phasing.  Could there be a bad internal winding if everything checked out okay or can a winding be going bad?  Or can you tell me if I am missing something?  This is a 50 HP motor, when troubleshooted there was no load on the motor.   

RE: 6 lead 2 speed motor

Please post all the motor name plate details.

* Women are like the police. They can have all the evidence in the world and yet they still want a confession - Chris Rock *

RE: 6 lead 2 speed motor

This is probably a Dahlander configuration where the motor is in delta connection for low speed and double star connection for high speed.

Do you have continuity between all six leads?

Best regards,

Mark Empson
http://www.lmphotonics.com

RE: 6 lead 2 speed motor

Yes I am with Marke , this sounds like a dahlander motor so maybe you are wrong connected the motor, if you have 6 leads the high speed could be obtained in delta connection and the low speed in star this is true if the motor is constant horsepower  but if the motor is constant torque the high speed be obtained in star and the low speed in delta.You could  have another connection called Variable torque High (2 Wye) and Low (1 Wye)

Note:

Constant Horsepower the horsepower is the same in any speeds.

Constant Torque Low speed horsepower is the half of high speed power.

Variable Torque Low Speed horsepower is one fourth  of high speed horsepower.

Regards

Petronila     

           

RE: 6 lead 2 speed motor


 You seem not familiar with this stuff, really. The fact some good boys out there rather mistakenly presume this as a simple wye-delta configuration,hence nothing the fact its 2 speed after a troubleshooting.
  Marke has pointed out the great possibility of the machine's wiring configuration it's a dahlander motor connection. Try to find out the continuity of its lead in which the quickiest way to confirm.


"..the more, the merrier" Genghis Khan

 

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources