4160V Generator Marathon (MTU) Failed during start up

[xnetfly]

From what I understand it seems that an eletrical sub provided a 4160V backup generator for the new addition at a hospital. When they performed the start up of the generator it failed electrically.

It seems this generator was put together in phases by MTU. Fabricated the enclosure in Florida, the engine was from Wisconsin and the flew in a belly tank. With that said they moved the engine around a bit. When they were shipping it back from FL to NC there was an accident on the highway that damaged the enclosure but caused no apparent damage to the gen set itself. This damage was repaired on site when it arrived at the hospital. Just recently they tried to operate the generator for a 24 hour run and when this happened it failed electrically. They said there was a big spark and the unit failed to operate. There is no apparent damage to the machine mechanically (bearings, rotors) but there does seem to be some paint chipping from the armature. We are at our our minds wit here. Not sure what happened and as far as being part of the facility department that needs to work on this piece of equipment we are struggling. Take a look at the picture. Any insight would be appreciated!!!! Thanks and love this site.

 

[dpc]

it failed electrically

I'm not sure on what your question is, but the first step is to get the generator manufacturer to send someone to the site to determine exactly what failed. Stator winding, rotor winding, exciter, end turn, field terminations, or what. Not knowing what factory and field tests were performed it is not useful to speculate from afar on the failure.

Presumably, this is under warranty, so the supplier will have to repair or replace to the owner's satisfaction. It would be good if the contractor has not yet been paid in full.

Once you find out what failed, let us know and you can get some tips on how to proceed.

David Castor

http://www.cvoes.com

 

[electricpete]

Take a look at the picture

I don't see any picture.

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[electricpete]

In addition to above questions, does the machine have a space heater and was there any attempt to assure the machine was dry (by inspection, test) before energizing.

Test results before and after failure...

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[edison123]

what dpc said.

Muthu

http://www.edison.co.in

 

[catserveng]

In general, I have found Marathon generators to be of good quality. That being said, based on your story it appears to have been some time since the unit left the factory.

I second electricpete's question, did it have generator space heaters, were the plugged in as soon as possible after arriving on site, and was the generator tested and inspected before being started?

I find it amazing how many standby generators go into service without taking those simple steps. Especially 4160 and 12kV units.

Just last week we took a replacement generator for a package off a truck from Minnesota, it was well wrapped, but had been on the road for about 10 days, and stuck somewhere due to some weather or road issues. As soon as it was in place we did a megger test, didn't test as well as we expected, turned on the heaters over the weekend, gave it a good lookover, and retested, now it reads ok.

Most of the Marathon folks I've dealt with are good, get them looking at it and share the results.

 

[JIMGEN]

I would be a little suspicious if it was involved in an accident. Hope it was not dropped.