The house next door dims !!!!!

[a.wayne3@verizon.net]

Very strange,a sub division all 2,000 sq. ft. avereage homes.All underground services.What is happeneing is that when the a/c or heat on one home kicks in the house next doors lights dim,not the home that the heat is kicking in but the one next door.....POCO has demand meters on these homes but they say there end is fine as far as initial check goes... Any ideas.....

 

[bob]

Re: The house next door dims !!!!!

The utiltiy probably has recording voltmeters installed. They are probably too slow the catch the dip in voltage. What happens is each time the A/C starts there is a voltage drop in the transformer. The amount of voltage drop depends on the size of the transformer and the %Z. If you have a Fluke meter, set it to read the MIN value
at the meter and at the transformer. There could be other problems but this check need to be done first.

 

[jimwalker]

Re: The house next door dims !!!!!

My mind says there is a bad nuetral on the house that blinks.Where did they hook to?I assume you have already re tightened all connections at both houses.This could be a real ball to run down.
How long do they dim ? less than a second or untill the ac or heat turns off?

[ December 21, 2003, 12:19 AM: Message edited by: jimwalker ]

 

[dnbob]

Re: The house next door dims !!!!!

I have a similar problem with my home also, when the neighbor starts a skill saw or any appliance similar in load, my lights dim. The only thing I could find is that there are 4 houses connected to one set of secondary conductors from the transformer ( 1 ped. in everyother yard), but there is potential for an additional 4 houses on that run, and I think the conductors are only 2/0 running from the transformer. It will probably only get worse. I haven't had the time to talk to the local utility, but with all their wire direct burial under driveways/sidewalks, there isn't much they could do anyway.

 

[a.wayne3@verizon.net]

Re: The house next door dims !!!!!

Nope not a loose or bad neutral in the house that dims there are almost 20 that are doing this.All on the same grid.The dimming lasts mmm 30 seconds or so,then it stops.I am thinking that the grid is the problem.There is no voltage drop hot to neutral or hot to ground.It stays steady but the lights dim...Ok I am confused

 

[jimwalker]

Re: The house next door dims !!!!!

are you saying 20 houses?

 

[bob]

Re: The house next door dims !!!!!

Wayne
An AC start up does not last for 30 seconds. If you check the voltage at the transformer when the unit starts you can either confirm its the utility or its something else.
Here in a URD subdivision each house get it own 4/0 AL service.

 

[jimwalker]

Re: The house next door dims !!!!!

Try this idea .In the house that dims plug in a 100 ft cord and carry it the next house .Hook up a light and dig volt meter ,now standing at the ac unit ,start it up and see if after starting the bulb is still dim. Or better yet give it a huge load like the heat strip.Just because TECO says it's not them doesn't rule them out.

 

[hurk27]

Re: The house next door dims !!!!!

I can only see one way this could happen is a bad/loss MGN on the pole before it gets to the area of these houses. or a bad connection on the hot primary side, But for it to be on the secondary side it would only effect the houses on the one transformer not 20.
By the way Allen I'm sure you know better than to go check for voltage at a transformer

 

[smclott]

Re: The house next door dims !!!!!

You might ask the utility to do a "steady state" volt drop calculation and a "starting" volt drop calculation. These are the terms we used at the utiltiy I worked for, but I am sure they were "our" terms,,, but they should be self-defining. Anyway, we had to consider the imp. of the txf, the length/size of UG sec & services, the loading. I know there were times that we had to add a par. run of secondary to the UG pedestal, or upgrade the txf. It seems like our SS volt drop and starting volt drop combined could not exceed 5% per the Public Ser Com.

 

[wire nut]

Re: The house next door dims !!!!!

We have almost the same problem at my house. First, just a little information. There are 5 houses/businesses fed by a single transformer on the pole. Over the past 4 years each of these houses upgraded from the 1940's vintage 60 amp services to 200 amp services (for home dwellings) or more (for business office space). My house is a legal duplex and currently has two new 200 services. Drops from the pole to the houses were changed by the power company. Houses all rewired to accommodate today's high amperage gizmos such as central a/c, modern kitchens, etc...

Whenver my neighbor's central a/c compressor kicks on, my house lights will dim for only a second. It took time to figure out the cause. I was drinking a beer on the front porch one hot summer night when I noticed my porch lights dim when I heard the neighbor's a/c compressor kick on. By the time I drank 1/2 case of beer, his a/c compressor cycled many times and I was 100% convinced this was the root cause of the problem. Also, after 1/2 case of beer I did not care since I was feeling good.

Latter in the summer when the power grid failed in my part of the country, we were in the dark. When power was restored to the grid, the initial load blew the fuse on the transformer and the 5 houses were in the dark until the power company visited the transformer.

I never approached my neighbor since we are not on speaking terms and never reported it to the power company. Since the load to the transformer has significantly increased over the recent years and no updates done on the pole transformer, I feel the transformer is overloading when the compressor kicks on. I was also thinking my neighbor's compressor may be drawing abnormally excessive amperage on startup too.

I just thought I'd post my experience. Sorry for putting all readers to sleep.

John
New Jersey

 

[charlie]

Re: The house next door dims !!!!!

Unfortunately, the person who checks for trouble is usually a trouble man who does a check with his instruments at that instant in time and he speaks for the electric utility. If you are having a problem with voltage drop and you believe it is the fault of the electric utility, it probably is and they can repair the problem, even if it is underground. The secondary can be increased in size, a larger transformer installed, another transformer installed that is closer, or a combination of all of the above. The problem can also be the distance from a substation or voltage regulator.

The bottom line is that the electric utility has a responsibility to repair the problem if it is their problem. A complaint to the public utility commission will usually get results if you have exhausted other avenues. But first, get into the engineering department to complain to them. They can order a recording voltmeter test that will stay on for about 3 days or even a week if necessary to get to the root of the problem.

The bottom line is that the trouble man is not equipped to give you a definitive answer.

 

[bob]

Re: The house next door dims !!!!!

Hurk

Why would you have concern regarding having the voltage checked at the transformer. You simply have the utility trouble man meet at the site and have him open the transformer. He along with Wayne could verify the voltage at the A/C startup.
Wayne could not do it by himself because the transformer cabinet is locked.

 

[jimwalker]

Re: The house next door dims !!!!!

BOLT CUTTERS
just joking

 

[charlie]

Re: The house next door dims !!!!!

Considering NFPA 70E is not used by electric utilities, our rules are different than for you. The trouble man does not know who you are and has not idea if you are OSHA qualified to be around MV equipment, why would he invite or permit you in the vicinity of an open and hot transformer?

Sorry guys, the voltage is checked at your place and you will have to take our word for what is going on at the transformer.

 

[a.wayne3@verizon.net]

Re: The house next door dims !!!!!

I didn`t check at the transformer,I checked at the affected home.At their panel...Tomorrow i have TECO engineers meeting me,I`ll let you know what is said

 

[jimwalker]

Re: The house next door dims !!!!!

Allen i believe it will end up being a TECO problem.2/0 is a bit small.Still waiting on call from Catus.Call me if there is a problem.

 

[a.wayne3@verizon.net]

Re: The house next door dims !!!!!

It is a teco problem.when the engineer got there he started to say it was a loose connection on our part.I responded with all of these homes.They put a moniter on the trans.and low and behold the voltage droppes to 105 v on 1 leg so they called for service.not sure what they did but problem solved

 

[hurk27]

Re: The house next door dims !!!!!

By Bob: Hurk

Why would you have concern regarding having the voltage checked at the transformer. You simply have the utility trouble man meet at the site and have him open the transformer. He along with Wayne could verify the voltage at the A/C startup.
Wayne could not do it by himself because the transformer cabinet is locked.

Well Bob you never know who is sandbagging in this forum (while I have the most respect for Allen not to do somthing like this It was just a chance to say that it would not be a good thing to do as Charlie pointed out) belive it or not we had a electrican (Who didn't work for us) do this by using climbing boots at a pole mounted transformer. He now has two fused knee caps one arm and is very lucky he's even alive.

That's Why.

[ December 23, 2003, 08:19 PM: Message edited by: hurk27 ]