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Sub transient reactance X”d worshiper.
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It is a normal metal building on a concrete slab. standard construction

HOLD UP, no center taps. yes, these are the pole transformers/ POCO xfmrs. 480V 3 phase. the secondary of the pots has ONLY 2 connections. #1 is to the other 2 pots and then ground #2 is to the 3 hot wires to the mill
I just need to ask one more question as annoying as it may seem.

two individual pole transformers?

or 3 individual pole transformers?
 

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Discussion Starter · #42 ·
I just need to ask one more question as annoying as it may seem.

two individual pole transformers?

or 3 individual pole transformers?
3 individual pots on the pole, only 2 secondary connections each, wye connected, service feeder is 3 hot wires ONLY ... no ground... no neutral
 

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Hackenschmidt
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3 individual pots on the pole, only 2 secondary connections each, wye connected, service feeder is 3 hot wires ONLY ... no ground... no neutral
At the pole, is the X0 / center of the secondary wye grounded?
 

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Discussion Starter · #44 ·
At the pole, is the center of the secondary wye grounded?
it has been several weeks since i looked at it. i actually dont remember. i was mostly interested in trying to believe what i was looking at .... 3 hot wires only, no other connections at the infeed weather head. Further more, if i had known how many questions this would generate, i would have brought pics and precise detailed explanations to start with. i brought all of this on myself for going off half cocked
 

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Discussion Starter · #45 ·
I want to thank every one for their interest, comments, and information. The next time i go to that mill (next town a half hour away). I WILL have pics and a detailed explanation of the connections for this service. Until then, i have already told you more than i know LOL
 

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Agreed. I have already experienced a single phase ground in the system. How or why it works was not the question
That’s not how it works here on ET, you may ask what time it is, but you’re going to get someone who’s going to tell you how a watch works.
 

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Discussion Starter · #47 ·
That’s not how it works here on ET, you may ask what time it is, but you’re going to get someone who’s going to tell you how a watch works.
that has become crystal clear to me. i have experienced it in other forums as well. guess i just forgot about that when i joined/asked
 

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Electrical Contractor
Trying to retire or at least slow down a bit, but life not cooperating
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Why don't you look thru all of the different transformer connection diagrams, then post a picture of the one you are describing?
As they say, a picture says a thousand words
 

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Discussion Starter · #49 ·
Why don't you look thru all of the different transformer connection diagrams, then post a picture of the one you are describing?
As they say, a picture says a thousand words
im sorry, but its because i dont remember all the details of the connections. one day i will go back to that mill and gather all the details and pics
 

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im sorry, but its because i dont remember all the details of the connections. one day i will go back to that mill and gather all the details and pics
While you're there, dig the ground up and make sure there is no ground connection to the building.
 

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Discussion Starter · #51 ·
While you're there, dig the ground up and make sure there is no ground connection to the building.
can you explain further ? or are you joking ? of course the building is grounded, its metal on a cement slab. however there is no hard-wired ground connection from the poco
 

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Discussion Starter · #52 ·
OK .... I finally found the thread that i was looking at before i joined yesterday (and a lot of you that have commented here also commented there)


this is the thread that prompted me to ask a question about the hook up i had ... this thread is in linework
 

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Discussion Starter · #53 ·
now to ask the question in a different way ..... is there such a thing as floating Y ?
 

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A connection from the X0s that ran along side the phase conductors would be called a neutral. You claim there is no "ground" from the utility. How do you know the utility ground and building ground are not bonded underground?
 

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Discussion Starter · #55 ·
A connection from the X0s that ran along side the phase conductors would be called a neutral. You claim there is no "ground" from the utility. How do you know the utility ground and building ground are not bonded underground?
ok its a serious question. answer, i dont. around here i have never seen poco do it that way. but then again i have never investigated this type of old service before. there is a bare neutral/ground wire in the 4plex service drop from transformer pole to weather head infeed pole. i have visually verified that it is not connected at either end.
it doesnt make sense to me that they would leave that unconnected and then bury a ground connection however
 

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ok its a serious question. answer, i dont. around here i have never seen poco do it that way. but then again i have never investigated this type of old service before. there is a bare neutral/ground wire in the 4plex service drop from transformer pole to weather head infeed pole. i have visually verified that it is not connected at either end.
it doesnt make sense to me that they would leave that unconnected and then bury a ground connection however
The neutral support wire you describe is a neutral, not a ground. If they didn't need the neutral it wasn't connected.

If the 480V service is supplying loads that do not require a neutral, say an MCC, why would one be installed? But normally you would still bond it to ground.

Back to the buried ground. Yes that's not the way it would be done today, but back in the day who knows what they did? There may be an entire ground grid installed at that location. Tell you what, instead of digging up the ground next time you're there:D, how about you string out a piece of wire between the utility and the buildings's ground and take a measurement. I don't have to tell you to check for voltage first.
 
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