Whats going on with my electrical service??

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  #1  
Old 07-10-18, 11:14 AM
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Whats going on with my electrical service??

I live in a small lakeside community that is about half empty except on Summer weekends. 20 years ago it was all small cottages, but they have been torn down and replaced with large air conditioned houses. They haven't done anything with the electrical service; in the winter I get 125v and in the summer much much less.

Last week the temperatures were unusually high and everyone was here; our voltage
got down to 103v everyday at about 6pm. I checked several neighbors and they were all like me.

Thursday there was a 10 hour backout of 300 houses in my neighborhood. When the power came back on, it was 106v; which was low for 1am. A half hour later it went out again for 30 seconds. It was then 109v. A half hour later it went out for 30 seconds. When it came back on it was 123v. A neighbor saw a utility truck at my pole during the last outage. It hasn't dropped below 117v since (that I noticed); but the weekend was cool, and yesterday was hot but not many people were around. Hopefully though it is really fixed.

Any guesses as to what has happened to improve my circumstances?
 
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Old 07-10-18, 11:57 AM
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Call your electric utility and tell them dangerously low voltages in neighborhood can cause house fires. Even the electric water pumps used to fight fires may fail. etc. etc. Raise fear of legal exposure for power issues.
 
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Old 07-10-18, 12:27 PM
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Any guesses as to what has happened to improve my circumstances?
Sounds like the power company lost some transformers and when replacing them found that the old ones were undersized.
 
  #4  
Old 07-10-18, 12:29 PM
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Not enough information to answer your question.

Using all of the words you stated, it is a matter of not enough power able to come to all 300 homes probably because the trunk lines (the medium tension, or primary, lines at the very top of the street utility poles) are not heavy enough for today's load.. Maybe more of a voltage drop if a transformer or transformer cluster on a utility pole outside the entire neighborhood got overloaded.

This is called a brownout.

It is also possible for a brownout or a blackout to affect just three to ten homes because the utility pole transformer or the secondary (120/240 volt) wires from that transformer serving just those houses is/are overloaded or fails. Perhaps the utility truck was there to change out that transformer.

Nothing is proved since you did observe any transformers being changed out.

It is not a solution to jack up the voltage considerably at the source with no other changes to be sure that there is always enough voltage at the far end. If this were done then during times of light load the voltage say halfway to the far end or even at the far end will be too high, like 130 volts.
 
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Old 07-10-18, 01:58 PM
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Unless you saw them pulling in new lines it's likely that they just swapped out an older transformer with a new, possibly larger one. Also possible they could have changed the taps a bit to increase the voltage but that might result in high voltages later as Allen mentioned.

The spec for residential voltage under normal conditions is 120V +/- 5% and 120V +7% / -13% under emergency conditions. Even the lowest voltages you measured are within the emergency ranges which are allowable for short time spans due to equipment failure, unusual weather, force majeure, etc.

It does sound like the electrical infrastructure in your area is pushed to the edge, but seems to still be within allowed limits.
 
  #6  
Old 07-10-18, 02:57 PM
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I neglected to mention that the same 300 houses had a 4 hour outage two days earlier, and one also 2 months ago. On those two we got 41v on each leg; on the most recent outages we got 0v.

I figured they replaced the transformer that fed the 300 houses during the 10 hour outage, and then adjusted the taps on "my" transformer during the subsequent 30 second outages. They couldn't have had time to replace the pole transformers could they?.
If that's what they did, and I used to get 125v in the winter, will I get 135v now unless they fix something else before then?
 
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Old 07-11-18, 10:23 AM
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I figured they replaced the transformer that fed the 300 houses during the 10 hour outage,
If so, most likely a transformer in the nearest substation. It only take an hour or two to change a pole mounted transformer.


then adjusted the taps on "my" transformer during the subsequent 30 second outages.
No, 30 seconds is not enough time.
 
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Old 07-11-18, 07:27 PM
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"... in the nearest substation ..."

In the U.S. transformers in a substation usually convert the usually 100k and higher transmission line voltage to typically 13K to 30K voltage with each transformer typically serving a few square miles. The next conversion is to (for homes) 120/240 volts by pole transformers each serving perhaps a few acres.

Individual streets or subdivisions might have fuses in the primary lines to help isolate some kinds of overloads. or the consequences of short circuits from falling trees.
 
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Old 07-12-18, 07:46 AM
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In that case, I'd recommend opening an issue with your state's public service or public utilities commission. That will be the regulatory agency in charge of oversight on this sort of thing. Also if you're in a development with it's own association or in an area served by a coop power company your neighborhood might be responsible for purchasing their own infrastructure so that's another avenue to investigate.
 
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