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14 % Harmonic Distortion at residential customer 1

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st50maint

Electrical
Nov 14, 2010
21
I have some high end audio equipment that displays the distortion of the incoming power.
My incoming power had always been between 2% and 3% distortion. Since a storm 4 weeks ago it has been 14% distortion. I have called LIPA (Long Island Power Authority) twice and have gotten the runaround. It seems that as long as my “appliances” are functioning, they are not interested in one residential customer’s whacky complaint.

2 questions;

1. Do I have the right to expect much lower distortion power from LIPA?
2. If so, any suggestions on how to get their attention?

Here is a picture of the incoming waveform:
untitled.jpg


 
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Sounds like your best option is to move or become an Amish farmer. On a more serious note, turn off all of your feeder circuits on your panelboard and then see what your getting. This may clue you in to where the problem may be occurring. If your THD problem disappears with all your feeder circuits off, then the problem resides from within. Also, check your neighbor's service. If your sharing a transformer with a neighbor, check out what his voltage THD is. If you find similar THD problems throughout the neighborhood, then you have more ammunition to complain to the local utility.
 
mmt019, Thanks for your suggestions. I have already done them. My neighbors also have the problem.

Here is the latest Email response from LIPA.

Thank you for contacting online services.
The initial investigation involved electric service securing the connections between the pole and the building structure.
This included checking and securing neutral and voltage connectors .
I have forwarded your information has been submitted to investigate electro magnetic field in the area.
Our interference personnel is now investigating the matter.

Ms Adams
Customer Online Services

 
st50maint said:
After 4 good months the problem has returned.
I'd guess that there is some customer with a 'dirty' (i.e. nonlinear) load out there on the system somewhere. Possibly only on one phase. Initially, during restoration following that storm, this customer was switched onto your phase. And now when the complaints ensue, LIPA just moves him to another phase, whereupon those customers start complaining.

LIPA may know who the culprit is. But they don't want to cause trouble by leaning on this customer. They'll just go on switching him around until they find a group of customers that don't mind the buzz.
 
5 days ago I went to a LIPA customer service office. The representative gave me a couple of names to call in the "Electric Construction" department.

The woman who answered my call actually seemed interested in my problem and said she would have the appropriate person call me back that day. I never did receive a call back. However, 2 days ago the problem was fixed. I now have 2.9% distortion.

I called LIPA back to thank them and hopefully find out what they did. The woman looked up the records for my address but did not find anything specific that had been done to correct the problem. So I do not know if my phone call helped or not. She did tell me to call back if it happens again.

Thanks for all the help on this forum.

 
This conversation or something like it probably took place. "John" and "Bob" are fictional employees.

Oct.2010- John- "What phase did you put BSPC (big@@@ single phase customer) on last night?"

Bob- "$%^^& I don't remember, it was raining down my back and I wanted to finish and and get back home.

Dec. 2010- John- "Bob, some guy is complaining about buzzing on his record player. Go see if maybe he is on the same phase as BSPC, and what you can do about it. I'm taking time off pretty soon for the holidays and don't want to hear about it then."

April 2011- Bob- "John, when I moved BSPC a few months ago, I put them on the same phase as my mother-in-law, We are going to have to do something."

John-"I don't care what you do, but don't put them on the same phase as MY house."

May 2011- John-" Bob, the record player guy is calling again. Maybe we can move your mother-in-law to a different phase, I'm getting tired of this #$%^".
 
Right on!

Only - it wasn't Bob and John. I recall Wayne and Chuck having those conversations...

Gunnar Englund
--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.
 
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