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Bob Hunt
10-28-2009, 01:18 PM
How far can the cable from the electric meter run on the outside of the house before penetrating the wall and feeding the main panel? I inspected a house today with an overhead entrance and the cable came out of the meter and ran along the house for about 15 feet before it entered the basement and then immediately into the panel box. I thought the limit was 5 feet from the meter to the panel without a disconnect.

Fred Warner
10-28-2009, 01:25 PM
It can encircle the house on the outside if the installer so desires. When it enters the house, it's a different ballgame. :)

Markus Keller
10-28-2009, 02:02 PM
Pretty sure 5', once it enters the house. On the outside like Fred said, could be almost anything. Meter to panel distances have been getting longer at least around here, especially on older homes/rehab. It was common to mount the meter socket ON the rear porch post or enclosure wall. People have been moving away from this and moving the service to a side elevation of the main structure. Problem has been that anytime a homeowner wanted to fix or re-side the back porch the service was there creating issues.

Jerry Peck
10-28-2009, 04:32 PM
As Fred said - outside can be as long as one wants it to be.

As Markus said - well, kinda like Markus said ... 5 feet inside, but that is not in the code, that is a common interpretation many AHJ use, the code actually says "nearest the point of entrance" of the service entrance conductors into the structure is where the disconnect would be located if inside the structure.

John Kogel
10-30-2009, 10:49 AM
Up here, we sometimes see the distance extended to the other side of the house by burying the conduit in concrete, like this one was going to be someday. :)

From this, I gather that buried in a slab is equivalent to being on the exterior??

Jim Port
10-30-2009, 11:28 AM
In the US you can cover the service entrance with 2" of concrete. This will then constitute being "outside" the building. This would allow a panel to be located on an interior wall and still be able to satify the need to keep the unfused length "as short as practical".

Jim Ulizzi
02-15-2013, 06:54 AM
I have a similar install right now.May have to remove meter main because homeowner already installed 3 wires in conduit from meter main to panel.Should have been 4. So if I install a regular meter socket the main panel will be 15' away in the garage. Then 3 wires should be ok.

Joe Funderburk
02-15-2013, 09:06 AM
As Fred said - outside can be as long as one wants it to be.

As Markus said - well, kinda like Markus said ... 5 feet inside, but that is not in the code, that is a common interpretation many AHJ use, the code actually says "nearest the point of entrance" of the service entrance conductors into the structure is where the disconnect would be located if inside the structure.

I'm an AHJ. In my jurisdiction, you'd have 10' past the meter to connect to an OCP device. That is a common enforcement policy in the Carolinas.

Jim Port
02-15-2013, 09:14 AM
I have a similar install right now.May have to remove meter main because homeowner already installed 3 wires in conduit from meter main to panel.Should have been 4. So if I install a regular meter socket the main panel will be 15' away in the garage. Then 3 wires should be ok.

If the conduit is metallic it can be used instead of a 4th conductor. If the conduit size is large enough you could also install the 4th conductor instead of changing the socket.

Jim Ulizzi
02-15-2013, 10:11 AM
conduit is 2" pvc w/ 2-4/0 and 1-2/0 not fishing another wire in there. It is buried under 18" of stone in the garage. The floor eventually will be concrete.Unless the inspector is hard core by the book I should be ok with my earlier post. This is one of these gray areas where safety is not being compromised at all.

Jim Port
02-15-2013, 10:31 AM
Four or five 4/0 can be installed in that size conduit depending on the insulation.

THWN-2 = 4
XHHW = 5

Jim Ulizzi
02-15-2013, 11:12 AM
maybe so Jim but the wires r already in and I was trying to avoid having to pull them out and refeed them with the 4th wire.

Joe Funderburk
02-20-2013, 11:25 AM
Is that 10' on the inside or 10' total? The NEC allows an unlimited length on the outside.

10' of cable from the meter to the panel inside the building envelope.

Jerry Peck
02-20-2013, 06:30 PM
I'm an AHJ. In my jurisdiction, you'd have 10' past the meter to connect to an OCP device. That is a common enforcement policy in the Carolinas.

As long as the service entrance conductors are outside the structure ... where do you get that there is any limited length to the service entrance conductors (provided voltage drop is taken into consideration for very long runs)?

There is *no* limitation stated in the NEC to base your AHJ opinion on until the service entrance conductors "enter" the structure, then, yes, that is a completely different issue - but there is *no* restriction for their length outside the structure.

Just wondering what code section you would cite as your documentation for not allowing more than 10 feet *outside* the structure after the meter?

And don't confuse "opinion" with "interpretation" as there is nothing in the code related to the above which needs an "interpretation", which means is it simply your "opinion" (and, apparently, the "opinion" of other AHJ in your area).

Jerry Peck
02-20-2013, 06:35 PM
10' of cable from the meter to the panel inside the building envelope.

To continue from my previous post after reading your follow-up post above: you have not stated how much is allowed *outside* the structure after the meter or how much is allowed *inside* after the point of entrance of the conductors.

Are you meaning that you allow 10 feet *beyond the point of entrance* of the service entrance conductors?

Just trying to decipher what you are actually stating as you refine your responses to clarify them.

Joe Funderburk
02-21-2013, 07:11 AM
To continue from my previous post after reading your follow-up post above: you have not stated how much is allowed *outside* the structure after the meter or how much is allowed *inside* after the point of entrance of the conductors.

Are you meaning that you allow 10 feet *beyond the point of entrance* of the service entrance conductors?

Just trying to decipher what you are actually stating as you refine your responses to clarify them.

I'll explain by illustration. If the meter is on one side of the house and the service entrance cable is routed through the attic to the garage on the other side of the house, that would be prohibited if the service cable is not protected with an OCPD. I'd make them put an OCPD (main disconnect) near the meter and the panel in the garage would therefore be a distribution panel.

Around here, most of the time the service entrance enters the house behind the meter, which is mounted on an exterior wall, to a panel on the inside of that same wall (typically the garage). However, sometimes the meter is on the other side of the house and they have to run the cable all the way across the house to get to the garage. That cable run on the interior of the structure needs over current protection.

Jerry Peck
02-21-2013, 08:03 PM
I'll explain by illustration. If the meter is on one side of the house and the service entrance cable is routed through the attic to the garage on the other side of the house, that would be prohibited if the service cable is not protected with an OCPD. I'd make them put an OCPD (main disconnect) near the meter and the panel in the garage would therefore be a distribution panel.

Actually, and to be more precise and accurate, it is prohibited to run the service entrance conductors through the attic (as you said), however, installing an OCPD at the meter ahead of the service entrance conductors makes those conductors no longer service entrance entrance conductors, which then makes it okay for them to run through the attic ... however ...

If they truly were service entrance conductor, there would be a neutral and two hot conductors, and now that they are no longer service entrance conductors - those conductors would require a separate grounding conductor - which means if those conductors were service entrance cable the cable would need to be replaced as the cable would not have contained a separate grounding conductor. ;)


Around here, most of the time the service entrance enters the house behind the meter, which is mounted on an exterior wall, to a panel on the inside of that same wall (typically the garage). However, sometimes the meter is on the other side of the house and they have to run the cable all the way across the house to get to the garage. That cable run on the interior of the structure needs over current protection.

And that cable would need to be replaced with proper cable with a grounding conductor as those conductors are now feeder conductors.

It is an error made during the installation of the service entrance conductors, with a follow-up error made in correcting the problem by leaving the service entrance cable when it needs to be replaced.