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Posted By: HCE727 Legal or not - 04/22/06 08:16 PM
I do some work in South Philly, were there is a lot of old brick fronts that need replacing. When the fronts are being replaced, the contractor puts pvc in between the two layers of brick, from the basement to the second floor and pops out with a 90, to where the service is to be attached. Noboby wants to see pvc or service cable on a new front. Then the EC comes in and does the service. Is this legal or not?
Posted By: earlydean Re: Legal or not - 04/22/06 08:46 PM
The disconnecting means and the OC device must be located inside or outside, nearest the point of entrance of the service conductors.
Service conductors have no short circuit or ground fault protection, so if there is a problem with the conductor insulation inside the conduit, it will spark and arc undetected until it melts clean through the PVC and may burn the building down. A safer installation would be rigid metal conduit, but that would only take a little longer to burn through.

[This message has been edited by earlydean (edited 05-30-2006).]
Posted By: iwire Re: Legal or not - 04/22/06 09:00 PM
I am not so sure it is a violation.

Quote
the contractor puts pvc in between the two layers of brick,

Quote
230.6 Conductors Considered Outside the Building.

Conductors shall be considered outside of a building or other structure under any of the following conditions:

(1)Where installed under not less than 50 mm (2 in.) of concrete beneath a building or other structure

(2)Where installed within a building or other structure in a raceway that is encased in concrete or brick not less than 50 mm (2 in.) thick

It sounds to me like this raceway is 'outside the building' and you can run service conductors as far as you want outside the building.

Bob
Posted By: earlydean Re: Legal or not - 04/22/06 09:03 PM
?

[This message has been edited by earlydean (edited 05-30-2006).]
Posted By: ShockMe77 Re: Legal or not - 04/22/06 09:53 PM
I notice this more and more as I like to look at services whenever I'm out and about. I don't like the design of hiding the pipe, but it sure seems like it's legal to do, as long as it's in pipe. SE cable is a different story.
Posted By: gfretwell Re: Legal or not - 04/24/06 05:02 AM
The only question I would have is how is that void between the brick verniers capped at the top? If this is a "chimney" into the attic it is still "inside" the building. If it is capped with more than 2" of mortar, brick or concrete, across the whole bay where the SE resides, it would be OK by me.
A wood top plate would not suffice.
Posted By: iwire Re: Legal or not - 04/24/06 09:52 AM
Greg I agree with you, we would have to see it to determine if it is indeed 'encased'.

That is why I carefully did not commit to a firm answer. [Linked Image]

I am not so sure it is a violation.

It certainly could be a violation but we also have to assume the local AHJ is on board with it.

Bob
Posted By: festus Re: Legal or not - 04/24/06 02:43 PM
I don't know if it is ok in Philly or not, but I sure miss the hoagies and cheesesteaks and the real pizza. I used to work in the shipyard until it closed,as a machinist, then got transferred to DC, became an electrician, and finally retired to NC. I don't know who the AHJ is in South Philly, but there was a time, I have been told, that a C note was required before the permit was signed off. Another thing to note is the homes don't look like much outside, but some contain 18 karat gold bathroom fixtures, imported Italian marble floors, front doors costing thousands etc...
Posted By: gfretwell Re: Legal or not - 04/24/06 04:15 PM
This is one issue we wouldn't have here in Florida. Masonry walls are capped with a 16" tie beam of poured concrete and rebar along with solid corners and window/door frames.
You never have more than 5' of wall without a poured cell.
Bury a pipe in there and it is "encased"
Posted By: e57 Re: Legal or not - 04/29/06 09:46 PM
This is the commentary from 230.70 A:
Quote
No maximum distance is specified from the point of entrance of service conductors to a readily accessible location for the installation of a service disconnecting means. The authority enforcing this Code has the responsibility for, and is charged with, making the decision as to how far inside the building the service-entrance conductors are allowed to travel to the main disconnecting means. The length of service-entrance conductors should be kept to a minimum inside buildings, because power utilities provide limited overcurrent protection and, in the event of a fault, the service conductors could ignite nearby combustible materials.
Some local jurisdictions have ordinances that allow service-entrance conductors to run within the building up to a specified length to terminate at the disconnecting means. The authority having jurisdiction may permit service conductors to bypass fuel storage tanks or gas meters and the like, permitting the service disconnecting means to be located in a readily accessible location. However, if the authority judges the distance as being excessive, the disconnecting means may be required to be located on the outside of the building or near the building at a readily accessible location that is not necessarily nearest the point of entrance of the conductors.

That said, I often run (required) RMC in the exterior WOOD walls, and have been allowed 35'+ inside the building with varying opions from different AHJ's. Good idea to always ask before jumping in too far.....
Posted By: gfretwell Re: Legal or not - 04/30/06 12:07 AM
There was a picture floating around a while ago showing a piece of RMC with the side blown out by a fault in a service conductor so that is not foolproof.
(IAEI Magazine maybe?)
Posted By: e57 Re: Legal or not - 04/30/06 02:31 AM
Nothing ever is... Foolproof that is.
Posted By: iwire Re: Legal or not - 04/30/06 02:37 AM
Quote
There was a picture floating around a while ago showing a piece of RMC with the side blown out by a fault in a service conductor

Was this it?

[Linked Image]

This is one of mine and I thought of posting it this thread but to be fair the available fault current here greatly exceeds that of a typical home service.

Bob
Posted By: e57 Re: Legal or not - 04/30/06 09:05 AM
Was this the 4-4" on the side of a supermarket? 'Cause of that one ever figured out?

Also to be fair, I have seen some bad demo accidents where they send in gorillas to demo a building and go too far too fast.

Diamond blade through encased conduit, wall supporting panels removed leaving panels in mid-air until they gave under thier own wieght. And a feeder with a 3/8 drill through it, and the MOCP failed to trip. I have also had one go off right in my hand. I was closing a cover and a kearny broke loose and popped through the tape against the cover I was holding in my hand. A little pinch against the split side of a split bolt through the tape blew a 2" hole in the cover. Went off like a grenade! Accually lucky to see this screen right now. But I can appreciate the hazards, but the risk is low, as in rare, for a fault to happen on its own, all by itself. Outside of over-load/fault by circuit use and failure of MCOP, in which it would happen anyway for simular results, inside, or outside.

[This message has been edited by e57 (edited 04-30-2006).]
Posted By: gfretwell Re: Legal or not - 04/30/06 04:11 PM
Bob That is not the one I was thinking about but I remember that one too. Yours is probably better [Linked Image]

All you really have to do is think of an arc welder. Even a fairly small one will easily blow a hole in an eighth to 3/16 inch of steel. A bolted fault would eventually open the primary fuse but an arcing fault could go on, virtually forever. I was in the Keys a while ago watching a service drop boiling and jumping around in a puddle for more than an hour. It was amusing for a bar full of patrons who were smart enough to watch from a safe distance. It was still burning when the PoCo finally got there to pull the disconnect. By then all the water in the puddle had boiled away and the asphalt was smoking.
Posted By: Alan Nadon Re: Legal or not - 04/30/06 04:43 PM
After the fire in the building caused the insulation to fail, the service conductors started cutting a hole in the rigid conduit while the firemen were pouring water on the blaze. Twenty feet of pipe split open before it was done.
This was on a downtown grid that the utility counldn't disconnect because the fire was too close to the cut outs. Transformer fuses finally opened.
In the after fire report the fire department was trying to make it an electrical fire because they saw the arcing.
The utility company and I clarified that the fire caused the arcing not the other way around.
Further investigation showed suspicious origin, possible arson.
They didn't blame that one on the electricians.
Alan--
Posted By: PCBelarge Re: Legal or not - 04/30/06 06:24 PM
The cable installers always seem to find these types of "hidden" service entrance conductors.
Posted By: CTwireman Re: Legal or not - 04/30/06 07:25 PM
One of the amazing things about Bob's pic is the molten metal splattered all over the wall. [Linked Image]

The cause of this one? I think the terrorists are to blame. [Linked Image]
Posted By: dlhoule Re: Legal or not - 05/02/06 06:16 PM
In Bob's picture, I would guess faulty insulation possibly damaged pulling it. All it takes is one bad piece of RMC with a burr of some sort.

I recently pulled new wire for some parking lot lights. I was amazed at the bad wire in that it looked to me like there was about 4" of copper gone and the insulation still intact. Maybe the water in the conduit kept insulation cool enough not to melt. I don't know. Any thoughts from you people?
Posted By: harold endean Re: Legal or not - 05/24/06 01:07 AM
Hey Greg,

The Sheriff is an AHJ is Norristown which I think is right outside of Philly. Also I remember reading somewhere that 1 or 2 states do this kind of service all the time. They install a service pipe right down in between the block and brick leaving only the meter pan and the service head exposed. I don't remember which state it was.
Posted By: HotLine1 Re: Legal or not - 05/26/06 08:35 PM
Here in NJ, the utility co's in my areas DO NOT allow the service conductors to be "hidden" before the meter. Yes, there are 'some' that are buried under vinyl siding, some under Drivit, and lord knows what else. Also some dangling from a siding job, and a few where the straps have gone away with age, but that is property maintenance.

John
Posted By: e57 Re: Legal or not - 05/29/06 07:25 AM
4" of copper gone and the insulation still intact."

Thats a tough one... The only, but not probable cause.... Long soak in bleach, or salt water. Or, more likely the electrolytic process in the water acting as electrode would in a battery. Or all of the above.
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