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Old 02-07-2019, 03:37 PM   #46
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Re: Normal voltage drop under load?


Have you replaced that meter pan yet ?

Getting replaced eliminates it as a potential problem. To replace it, most POCOs cut the splice at the service point. Assuming crimp connectors, replacing the splices eliminates another point of possible resistance.

BTW, the comment by someone that your POCO is regulated by the PUC is not necessarily correct. MLGW isn’t a public utility company. They are a Municipal Power District or Authority. A Muni (or other governmental power district/agency) is not typically regulated by the PUC.

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Old 02-07-2019, 03:52 PM   #47
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Re: Normal voltage drop under load?


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Originally Posted by tmittelstaedt View Post
No, that is quite wrong.



The "service drop" is all the wire from the pole to the meter socket. The meter socket and meter itself is the actual dmarc point, not some random splice hanging in the air.



While it is true that many power companies require the builder to provide the weatherhead and the conduit from it to the meter as well as the cabling from the meter to the overhead service lateral, the second that they connect to this cable the ENTIRE CABLE FROM THE POLE INCLUDING THE BITS YOU BOUGHT BECOMES THEIR PROPERTY. That IS the "service drop" They make you pay for it because they can - because they have political power and forced the municipalities to sign off on it, and because when you are actually building a house you have to schedule in your electricians who are installing the panel and it's too difficult to get the PoCo techs and the builders electricians to meet on the same day and time. So a de-facto convention has grown up of making the builder pay for the wire going from the splice to the meter base but do not mistake that for actual ownership which is different.



Think about it. If the actual dmarc was the splice overhead and I owned the cable from the splice to the meter then I would have the legal right to tap off MY PROPERTY before the meter and use the power. That is why legally the power company owns any and all cabling from the pole to the meter socket. YOU own the cable from the meter socket to the inside of your house.



In addition you might notice that the jacket of the cable is sunlight resistant. You don't need that inside a conduit where there is no sun!! That cable is manufactured for use in conduit and use in overhead laterals. It's current rating expects use in overhead laterals. And no matter how much cooling an overhead lateral gets, it doesn't make 2/0 right for 200A MAYBE 3/0 is OK but that's pushing it particularly for long laterals. The OP's power company is just cheapskates I don't understand why you are defending them. Some beancounter at the PoCo decided that the average length of service lateral is X and voltage drop over that average is barely just within tolerance so they thought they would save a few bucks on laterals. That may be OK for everyone with a lateral that X length or shorter but not for the ones with longer laterals.



Your just confused by the sloppy writing in the blurb and you aren't thinking about the logic involved here. This wire sizing issue isn't an issue in most of the PoCo distribution system anyways since they are running 1000's of volts in the distribution system to the transformers and that only needs thin wire.



The claim that the homeowner isn't expected to ever use 200A is very sketchy anyway. They paid for 200A service and they should be able to get it. And as I already stated if the OP actually put close to 200A load on there the voltage drop would be out of even your extremely generous allowance.



Anyway, this is all academic anyway because the OP measured the voltage drop at currents well under the max capacity of 2/0 AL. But if they are going to be cheap on the service drop then they probably are cheapskates throughout their distribution system which is the real problem.
Get some damage to the wire from the weather head down to the meter and you will see how quick the POCO tells you it is yours

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Old 02-07-2019, 03:52 PM   #48
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Re: Normal voltage drop under load?


Quote:
Originally Posted by Oso954 View Post
Have you replaced that meter pan yet ?

Getting replaced eliminates it as a potential problem. To replace it, most POCOs cut the splice at the service point. Assuming crimp connectors, replacing the splices eliminates another point of possible resistance.

BTW, the comment by someone that your POCO is regulated by the PUC is not necessarily correct. MLGW isnít a public utility company. They are a Municipal Power District or Authority. A Muni (or other governmental power district/agency) is not typically regulated by the PUC.
I haven't replaced it yet. Great points though! I agree!
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Old 02-07-2019, 03:54 PM   #49
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Re: Normal voltage drop under load?


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Originally Posted by rjniles View Post
Get some damage to the wire from the weather head down to the meter and you will see how quick the POCO tells you it is yours

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Unfortunately you are right. My understanding was that all of the cables up to the meter was theirs, but they told me that it's mine
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Old 02-07-2019, 04:39 PM   #50
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Re: Normal voltage drop under load?


OP.......is the dimming every time there is a load or is it intermittent (sometimes it does and sometimes it doesn't) based on the same load?

If not intermittent (ie does it every time) then you probably have a resistance problem....poor connection, undersized wire, etc.

If it is intermittent then I still think that an undersized transformer may be the cause of your dimming especially since another service load is on that can. Do the lights ever dim without a load applied? Another indication of undersized can.
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Old 02-07-2019, 04:47 PM   #51
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Re: Normal voltage drop under load?


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Originally Posted by DanS26 View Post
OP.......is the dimming every time there is a load or is it intermittent (sometimes it does and sometimes it doesn't) based on the same load?

If not intermittent (ie does it every time) then you probably have a resistance problem....poor connection, undersized wire, etc.

If it is intermittent then I still think that an undersized transformer may be the cause of your dimming especially since another service load is on that can. Do the lights ever dim without a load applied? Another indication of undersized can.
Great point! The lights do consistently dim when a load is applied. There is nothing intermittent about it. The voltage does vary by a few volts throughout the day, but I consider that normal.
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Old 02-08-2019, 09:40 AM   #52
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Re: Normal voltage drop under load?


Such a helpful post!
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Old 03-12-2019, 08:50 PM   #53
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Re: Normal voltage drop under load?


Ok I have an update. I replaced my old crappy meter box with the new one that they gave me, which is a lot nicer than the old one. The contacts are heavier, it holds the meter much tighter, the metal looks shinier, and the box is much nicer to look at since it is new and nicely painted.

However, as nice as the new box is, it didn't fix the problem. The lights still dim just as bad under load. The power company is (unsurprisingly) being crappy and unhelpful too. They are now trying to say that I need to replace my 4/0 gauge aluminium cable from their lines to my meter box and electrical panel with copper cables.

I asked them why my 15 or so feet of 4/0 aluminium cables would be the problem when they have probably 100 or 150 feet of 2 gauge aluminium cables running to my approximately 15 feet of 4/0, but they just kept saying "Copper wire of the same size can handle 30% more current than aluminium wire". But they didn't convince me that my short and fat wire is the problem rather than their long skinny wires made out of the same material.
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Old 03-12-2019, 09:54 PM   #54
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Re: Normal voltage drop under load?


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I asked them why my 15 or so feet of 4/0 aluminium cables would be the problem when they have probably 100 or 150 feet of 2 gauge aluminium cables running to my approximately 15 feet of 4/0, but they just kept saying "Copper wire of the same size can handle 30% more current than aluminium wire". But they didn't convince me that my short and fat wire is the problem rather than their long skinny wires made out of the same material.

I went back and reread some of your earlier posts. In #17, you said you measured a voltage drop of 12V under a 91A load. If the poco service drop is 150' of #2 AL wire, you'd expect a drop of just 7V through their wire. I doubt your 15' of 4/0 is providing the additional 5v drop, unless there is a bad connection between them.


This makes me think that the transformer is being overloaded and can't deliver what you need.



Has the meter been sealed? it would be nice to measure the voltage at the meter under load. Then there would be no doubt about whose problem it is.
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Old 03-12-2019, 10:13 PM   #55
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Re: Normal voltage drop under load?


if he is really careful he could measure at the connection point.
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Old 03-13-2019, 09:57 AM   #56
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Re: Normal voltage drop under load?


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I went back and reread some of your earlier posts. In #17, you said you measured a voltage drop of 12V under a 91A load. If the poco service drop is 150' of #2 AL wire, you'd expect a drop of just 7V through their wire. I doubt your 15' of 4/0 is providing the additional 5v drop, unless there is a bad connection between them.


This makes me think that the transformer is being overloaded and can't deliver what you need.



Has the meter been sealed? it would be nice to measure the voltage at the meter under load. Then there would be no doubt about whose problem it is.
Great info, thanks. The meter has not been sealed, so I could check voltage coming into the meter. However, the meter is being fed by my 4/0 cable, so even if the voltage coming into the meter is low they could still blame it on my wire. I asked them to test the voltage where their wires connect to mine while the system was under load to prove that it was measurably higher than at the panel, but they refused and said "Even if the voltage at the connection point is the same as at the panel, you still need to upgrade your cables to copper because it could handle 30% more power".

So not that I am going to, but if I wasted my time and money replacing the cables with 4/0 copper, then I wonder what they would blame it on. I am sure they wouldn't say "Actually since everything on your side is new and up to spec, the problem clearly was on our side all along. We are going to check voltages to find the problem and fix it"
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Old 03-13-2019, 10:50 AM   #57
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Re: Normal voltage drop under load?


Quote:
Originally Posted by DanS26
Again....take a look at the can...how many other services are being provided by that particular transformer. Follow the wires. If you are the only one then it is not the problem.

Quote:
There is 1 other house running off of this transformer.

Maybe I missed it but have you consulted with your neighbor to see is the same thing happens at his house? If not, I would suggest that you do so.
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Old 03-13-2019, 11:16 AM   #58
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Re: Normal voltage drop under load?


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Originally Posted by hkstroud View Post
Quote:
Originally Posted by DanS26
Again....take a look at the can...how many other services are being provided by that particular transformer. Follow the wires. If you are the only one then it is not the problem.




Maybe I missed it but have you consulted with your neighbor to see is the same thing happens at his house? If not, I would suggest that you do so.
Honestly I never thought to. I will ask him if he noticed this and report back. However, his house is much closer to the transformer than mine, so the cables going to his house are much shorter, probably 75 feet or so, and the wiring would therefore have much less of a voltage drop. Great idea to ask!
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Old 03-13-2019, 11:24 AM   #59
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Re: Normal voltage drop under load?


Forget the entrance cable sizes for the moment. You are talking about amperage (total at any one time) that could be carried on 8 or maybe 6 gauge wires without a significant voltage drop.
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