×
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

How to megger a 80 DGDA Onan Cummins generator

How to megger a 80 DGDA Onan Cummins generator

How to megger a 80 DGDA Onan Cummins generator

(OP)
I need help on getting some information on how to megger the stator windings on the above mentioned model generator.

Thank you

RE: How to megger a 80 DGDA Onan Cummins generator

I am not sure what you are asking. If it is how a meggar testing is done, I have explained below.

Meggar is basically measurement of insulation resistance of the machine. The meggar leads are to be connected between the terminal & earth and the readings noted. Obviously, it is done with the machine isolated. Incase the neutral is connected to earth, either directly or through a neutral grounding resistor, that needs to be isolated before the testing. The insulation resistance value will stabilize in few minutes. If it is a big machine the reading is taken over 10 minutes. Small machines, even 1 minute readings can be considered sufficient.

Depending on the voltage rating of the generator, the meggar voltage will vary.

Hope that answers your question.

Anand Sekhar

RE: How to megger a 80 DGDA Onan Cummins generator

From the hands on point of view;
1:> disconnect the grounding jumper if present.
2:> Disconnect the Automatic Voltage Regulator leads.
3:> Disconnect the wiring to the panel meters (Voltmeters, Power Meters and anything with a voltage connection.
4:> Consider disconnecting the leads to the main circuit breaker.
5:> There should be nothing connected to the windings except other windings, and possibly the main breaker if that is your choice.
You may megger the windings as a group, or choose to megger them individually. Group checking is fast. Individual checking may show up a winding with a much lower resistance to ground than the others even though it is acceptably high. The choice of methods depends on the reason for the test in the first place.
respectfully

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