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what is the solutiom

what is the solutiom

what is the solutiom

(OP)
I have a 90 hp 400v 130A electric motor in my installation. the line voltage is average 170v on phase to neutral. in other words low line voltage is being experienced.  what mehod do you guys think i could adopt to solve this problem. will a transformer do? if yes what type?  

RE: what is the solutiom

We would need more information to try and solve this, 100 volts off of nominal is a lot.  

Why is the line voltage low?  Is it low only when you run the motor or is it low before you start running the motor?  

Is the power supply big enough to supply the motor?  

Did you get supplied with the wrong voltage motor and that's what you want to fix?

We need some hints before suppling answers.

RE: what is the solutiom

Quote:

...We need some hints before supplying answers.
I think that should read "We need some answers before supplying hints!". The answers can only come from someone who is there and able to troubleshoot the entire system. But other than that, I wholeheartedly agree. You (lukmon) don't know if you are looking at a cause or a symptom.

"If I had eight hours to chop down a tree, I'd spend six sharpening my axe." -- Abraham Lincoln  
For the best use of Eng-Tips, please click here -> FAQ731-376: Eng-Tips.com Forum Policies  

RE: what is the solutiom

I do not understand why you measure L-N voltage. Have you checked L-L voltage? What does it say? Is it sqrt(3)*170 V or is it some other voltage?

Is this a DOL motor or do you have a soft starter or a VFD involved?  

Gunnar Englund
www.gke.org
--------------------------------------
100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...

RE: what is the solutiom

Where is the neutral you're measuring to?  I would not expect to see a neutral pulled to a three-phase motor.

I would double check that the system you're connected to is in fact a 480V grounded wye.  If it is, that voltage is cause for concern.

-John

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