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Sound Reinforcement - Forums for Live Sound Professionals - Your Displayed Name Must Be Your Real Full Name To Post In The Live Sound Forums => AC Power and Grounding => Topic started by: Jonathan Hiemberg on June 25, 2017, 06:39:04 pm

Title: 50kw generator trouble shooting question
Post by: Jonathan Hiemberg on June 25, 2017, 06:39:04 pm
Afternoon,


Before I get into this: Rest assured I have an electrician who I'm told specializes in large generators and maintains them for the local county coming tomorrow to look at this problem.


I would like to get my head around this problem because the electrician will be meeting with my staff as I will be away.


Our 50kw Generac has given us an intermittent problem where it will run fine but simply produce no power (actually 12v, but that's it).


It happened once last year, but mysteriously 'went away' for no apparent reason. We chalked it up to loose connections somewhere and went on.


We've put 100 hours on it since then (still only 384 total), and now it's back and (it seems) to stay.


The techs discovered the problem while it was out in the field, and had no backup, so started googling. Read lots about 'flashing' a generator that has lost it's residual magnetism.


The 'hand drill' method did nothing, but the method described here (https://www.auroragenerators.com/blogs/generators/119728961-fixing-portable-generator-that-have-no-voltage-output) had fair results.


But - what would happen is that while the 12v from the battery was connected to the generator brushes it would generate 110v, as soon as the 12v was removed there was no power output.


So - again - I'll have the tech by tomorrow, but any thoughts ahead of time to help me understand this problem?


Also - is there something we could be doing to cause this - or avoid doing - or is this just a regular maintenance issue?


Thank you!
Title: Re: 50kw generator trouble shooting question
Post by: Kemper Watson on June 25, 2017, 08:10:46 pm
Afternoon,


Before I get into this: Rest assured I have an electrician who I'm told specializes in large generators and maintains them for the local county coming tomorrow to look at this problem.


I would like to get my head around this problem because the electrician will be meeting with my staff as I will be away.


Our 50kw Generac has given us an intermittent problem where it will run fine but simply produce no power (actually 12v, but that's it).


It happened once last year, but mysteriously 'went away' for no apparent reason. We chalked it up to loose connections somewhere and went on.


We've put 100 hours on it since then (still only 384 total), and now it's back and (it seems) to stay.


The techs discovered the problem while it was out in the field, and had no backup, so started googling. Read lots about 'flashing' a generator that has lost it's residual magnetism.


The 'hand drill' method did nothing, but the method described here (https://www.auroragenerators.com/blogs/generators/119728961-fixing-portable-generator-that-have-no-voltage-output) had fair results.


But - what would happen is that while the 12v from the battery was connected to the generator brushes it would generate 110v, as soon as the 12v was removed there was no power output.


So - again - I'll have the tech by tomorrow, but any thoughts ahead of time to help me understand this problem?


Also - is there something we could be doing to cause this - or avoid doing - or is this just a regular maintenance issue?


Thank you!

You should post this in the power/grounding section ..