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Ross Neag
01-31-2011, 09:32 PM
Does 230-51(a) refer to just exposed, insulated SEC or the mast as well? My Q is a service mast that DOES NOT have an attachment to the home 12" or less from the weatherhead (it's about 3 feet).

Speedy Petey
02-01-2011, 04:21 AM
Does 230-51(a) refer to just exposed, insulated SEC or the mast as well? My Q is a service mast that DOES NOT have an attachment to the home 12" or less from the weatherhead (it's about 3 feet).230.51(A), and all of section"IV", are regarding "conductors", so a raceway or mast would not be part of that.

In fact, 230.24(A) expressly prohibits a point of attachment on a mast that is closer than 18" from a roof. A mast that is 3' out of a roof without additional support is perfectly normal.

http://ecmweb.com/nec/code_qa/230-24Ax3-UN230-11web.jpg
©Mike Holt

Jerry Peck
02-01-2011, 07:24 PM
In fact, 230.24(A) expressly prohibits a point of attachment on a mast that is closer than 18" from a roof.


"expressly prohibits a point of attachment "

Actually, that is incorrect ... ;) ... that section prohibits the conductors from being within 18 inches of the roof, the "point of attachment" may be within 18 inches provided that the conductors are not within that 18 inches.

Speedy Petey
02-01-2011, 08:45 PM
"expressly prohibits a point of attachment "

Actually, that is incorrect ... ;) ... that section prohibits the conductors from being within 18 inches of the roof, the "point of attachment" may be within 18 inches provided that the conductors are not within that 18 inches.You are very right. I guess you could say the POA is along for the ride as far as the 18" is concerned. ;)

Ross Neag
02-03-2011, 04:46 PM
Sorry Gents,

Here is the pic and I should have clarified that this was below a roof line and secured to the home at the NW corner. I'm not sure if it needs attachment 12" or less from the weather head or within 30" of same.

FYI- that casement is hinged closest to the SEC (opens AWAY from) and would make for a very valiant effort to reach in mid air.

Jerry Peck
02-03-2011, 05:51 PM
FYI- that casement is hinged closest to the SEC (opens AWAY from) and would make for a very valiant effort to reach in mid air.
Regardless of which way it is hinged, the window opening needs to meet this: (bold and underlining are mine)
- 230.9 Clearances on Buildings.
Service conductors and final spans shall comply with 230.9(A), (B), and (C).
- - (A) Clearances. Service conductors installed as open conductors or multiconductor cable without an overall outer jacket shall have a clearance of not less than 900 mm (3 ft) from windows that are designed to be opened, doors, porches, balconies, ladders, stairs, fire escapes, or similar locations.
- - - Exception: Conductors run above the top level of a window shall be permitted to be less than the 900-mm (3-ft) requirement.
- - (B) Vertical Clearance. The vertical clearance of final spans above, or within 900 mm (3 ft) measured horizontally of, platforms, projections, or surfaces from which they might be reached shall be maintained in accordance with 230.24(B).
- - (C) Building Openings. Overhead service conductors shall not be installed beneath openings through which materials may be moved, such as openings in farm and commercial buildings, and shall not be installed where they obstruct entrance to these building openings.

Ross Neag
02-03-2011, 06:17 PM
Got it. Thanks JP.

Patrick McCaffery
02-05-2011, 03:56 AM
JP,
As an inspector I know that I only need to report the concern, my questions are:
1. This looks like a fairly new dwelling, how would it get a C of O?
2. Does the Service provider normally install the mast?
3. Who would be responsible to correct the situation?
I value your opinion and certainly appreciate the information that you provide to this site.
Thank you

Speedy Petey
02-05-2011, 07:16 AM
It might just be the angle of view, but that looks to me like a fixed window. That or casement.

Ross Neag
02-05-2011, 08:53 AM
All,

It is a casement window that opens AWAY from the service mast. I didn't call it out as I feel it didn't pose a threat. Here come the fireworks. If I go back and measure it and find that it's 35 3/4" from the window rough opening, well...

I just don't live in that world of 1/16" here and 3/16" there, PRACTICALLY speaking. Exposure? Sure I'm not immune to it. I'm also interested to hear how other HIs would have reported this WITHOUT a measurement. Would it have made your list with or without knowledge of this thread and our discussion?

Jerry Peck
02-05-2011, 06:58 PM
1. This looks like a fairly new dwelling, how would it get a C of O?

I don't know, I was not there. ;)


2. Does the Service provider normally install the mast?

No, the electrical contractor does.


3. Who would be responsible to correct the situation?

An electrical contractor, who will need t5o work with the power company to turn the power off and then back on.


It might just be the angle of view, but that looks to me like a fixed window. That or casement.

A fixed window would not be a window "which is designed to be opened" and thus would not have a clearance requirement.

A casement is a window which is designed to be opened and thus would require the clearance - regardless of which way the casement opens.

Speedy Petey
02-05-2011, 08:15 PM
A fixed window would not be a window "which is designed to be opened" and thus would not have a clearance requirement.

A casement is a window which is designed to be opened and thus would require the clearance - regardless of which way the casement opens.Yeah, that was pretty much my point. I should have been clearer.
Thanks Jerry. :)

bob smit
02-07-2011, 02:46 PM
Just a note; if the service mast is to be (or is being) used as the service drop support, then the mast supports themselves shall be listed for this use. As always, point of attachment to be below the service head.