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Discussion Starter · #1 ·
The rural cooperative POCO installed a new transformer, a new meter, and new 4 awg copper wire in the meter loop (on a pole) to be used as a feeder to the property (after the main service disconnect). The cooperative also advised that the transformer is sufficient for 125 amp service.

I installed a 125 amp main breaker panel immediately below the meter and used 1 AWG from the bottom of the meter to the main service breaker.

According to my review of NEC 310.15(B)(16), I can't find any column where 4 AWG copper is sufficient for 125 amps. So which of the following is the correct scenario:

1. The property will not have 125 amps available due to insufficient cable installed by the cooperative?

2. I am mis-interpreting the correct conductor size for a 125 amp service?

At the moment, I don't know the size of the wires coming from the transformer to the top of the meter. I'll have to check that.
 

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Discussion Starter · #3 ·
POCO has their own rules for wire sizing.
That may be. So now the question is which 'rules' are correct? Is the 4 AWG going to melt away if the respective amperage listed in the NEC table is exceeded?

I guess this brings up the question of 'ownership' or 'responsibility'. The 4 AWG was installed in the meter loop assembly (service head, pipe, meter socket), I suppose, as a favor to the customer?? The 4 AWG is utilized AFTER the service disconnect. To whom does it belong??
 

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Lic Electrical Inspector
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AS stated, the POCO follows a different set of rules. Their service drop is also considered "free air" which allows higher ampacities.
 

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From the weatherhead down is normally the customers responsibility.
 

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Discussion Starter · #8 ·
So now there are conflicting answers. If the meter loop is customer's responsibility then why do POCO rules apply to sizing the conductors?

Perhaps I'll inquire with POCO.
 

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A "Handy Husband"
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So now there are conflicting answers. If the meter loop is customer's responsibility then why do POCO rules apply to sizing the conductors?

Perhaps I'll inquire with POCO.
They don't, those conductors are sized by the NEC and are not free air whether in conduit or SE cable. And are installed by the customer. I know as I had to replace mine when a tree pulled my service down and bent my mast. Bent the mast and squashed the conductors.

In my service area if the service is under ground, the POCO supplies and install the feeder to the meter. Customer digs and provides the conduit.
 

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Discussion Starter · #11 · (Edited)
Kyle_in_rure said:
Most likely there is a junction right at the weatherhead, and thicker wire goes down to the meter.
Yes. But that's not the issue. It's the conductors leaving the service disconnect and going to the house.

Either way, it is really nothing worth worrying about.
Except for compliance with the NEC. And perhaps melting the insulation. Which might result in a short circuit. Which would create a loss of power and create more work. You're right...nothing to worry about.:icon_rolleyes:
 

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E2 Electrician
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Yes. But that's not the issue. It's the conductors leaving the service disconnect and going to the house.



Except for compliance with the NEC. And perhaps melting the insulation. Which might result in a short circuit. Which would create a loss of power and create more work. You're right...nothing to worry about.
Just leave it alone, you're not grasping the concept.
 

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E2 Electrician
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Has the concept been communicated effectively? Seriously, what am I missing?
Yes it has....

The rural cooperative POCO installed a new transformer, a new meter, and new 4 awg copper wire in the meter loop (on a pole) to be used as a feeder to the property (after the main service disconnect). The cooperative also advised that the transformer is sufficient for 125 amp service.
The Poco does not abide by the NEC.
 

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Discussion Starter · #15 · (Edited)
Yes it has....



The Poco does not abide by the NEC.
No it hasn't...

Have you read the other posts which state that these conductors are not the POCOs responsibility? Which posts are accurate?

The concept is...did the POCO install the wrong conductors, and is it the customer's responsibility to make it right?

Are these 4 awg conductors subject to the NEC or to the POCO rules? Does the fact that POCO installed them automatically exempt them from NEC requirements?
 

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Can you re-install thicker wires from the weatherhead through the conduit down the side of the house? Nothing forbids installing thicker wires even though the pole transformer has a more limited amperes rating.

Two small a wire size runs into two issues: overheating and voltage drop.

Hanging in free air, wires can take more current before overheating becomes a concern. There is probably a chart somewhere that specifies the desired size for free air.

Voltage drop depends on the length of the wires as well as the thickness (and material). With 4 gauge copper and 120/240 volt service the run from the transformer to the meter can be up to about 115 feet (230' round trip) and voltage drop is within three percent for 125 amperes which is acceptable. Voltage drop is actually a little worse if you are drawing the maximum 125 amps (at 120 volts) on one side (from one leg) of the service and somewhat less on the other side.

There may be another one or two percent lost within the wiring inside the house and you want to keep the total below 5%.

It is rare that you will be drawing the full 125 amps on either side.

(4 gauge copper has about 0.25 ohm for 1000 feet. At all times in any portion of an electrical circuit including a section of wire, the voltage dropped in that section equals the current flowing through times the resistance.)
 

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E2 Electrician
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No it hasn't...

Have you read the other posts which state that these conductors are not the POCOs responsibility? Which posts are accurate?

The concept is...did the POCO install the wrong conductors, and is it the customer's responsibility to make it right?

Are these 4 awg conductors subject to the NEC or to the POCO rules? Does the fact that POCO installed them automatically exempt them from NEC requirements?
Did it get inspected? If POCO does the installation, then it doesn't abide by the NEC... end of story.


Besides all of that said, it will never be an issue in the real world....
 

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Discussion Starter · #18 · (Edited)
Did it get inspected? If POCO does the installation, then it doesn't abide by the NEC... end of story.


Besides all of that said, it will never be an issue in the real world....
POCO installation:
Inspected = I don't know.

My installation of the 125 amp disconnect:
Permitted = yes.
Inspected = no.

Which will not be an issue? Compliance? Or wire melting? Or both?

Sometimes images help.
View attachment conductor sizing.pdf
 

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E2 Electrician
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POCO installation:
Inspected = I don't know.

My installation of the 125 amp disconnect:
Permitted = yes.
Inspected = no.

Which will not be an issue? Compliance? Or wire melting? Or both?
I don't see the issue since the POCO did the installation. The NEC is ridiculously overkill. Why didn't the job get inspected?
 

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Discussion Starter · #20 ·
I don't see the issue since the POCO did the installation. The NEC is ridiculously overkill. Why didn't the job get inspected?
Good to know the NEC has lots of cushion...I guess.

No inspection occurred because I assume the inspector simply wants the permit money. Its in a rural location but it is incorporated into the town limits. Maybe he is lazy? I don't know...he is more than welcome to come inspect...he just doesn't do it. Write a check...get a permit filed...do the work. Small town culture.
 
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