we have 11 KV ABB motor driving a big KSB water pump, stopped and could not be restarted again. after megger test it found an open circuit.

we are going to open the motor for primary inspection. is there any advice or recommendations for what are the main points or parts to be checked?

 

Ahdash... to start:

o Age
o Size (to ascertain adequacy of pig-tail wire)
o # Total Starts and condition (on or off load)
o Noises during start.
o Time to accelerate.
o DOL or reduced voltage starting.
o kVA/Hp ratio.
o Operational history.
o Protection device operation.
o Maintenance history

Regards,
Phil Corso

 

Ahdash... before responding to your "Tap-Changer" post, how about a status report on this thread!

Phil Corso

 

Dear Phil Corso,
Thanks for your comments, I found it very useful.

[email protected]

 

What was the problem?

 

We found the stator winding burnt due to high voltage and the surge protection was faulty. Rewound and put back in service.