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mathew stouffer
05-28-2010, 03:58 PM
If this Romex is rated for UV exposure, is this an acceptable instalallation.

Jerry Peck
05-28-2010, 04:26 PM
No.

That does not meet the supporting and securing requirements - NM cable is required to be supported and secured every 4-1/2 feet

- 334.30 Securing and Supporting.
- - Nonmetallic-sheathed cable shall be supported and secured by staples, cable ties, straps, hangers, or similar fittings designed and installed so as not to damage the cable, at intervals not exceeding 1.4 m (4½ ft) and within 300 mm (12 in.) of every outlet box, junction box, cabinet, or fitting. Flat cables shall not be stapled on edge.
Sections of cable protected from physical damage by raceway shall not be required to be secured within the raceway.
- - (A) Horizontal Runs Through Holes and Notches. In other than vertical runs, cables installed in accordance with 300.4 shall be considered to be supported and secured where such support does not exceed 1.4-m (4½-ft) intervals and the nonmetallic-sheathed cable is securely fastened in place by an approved means within 300 mm (12 in.) of each box, cabinet, conduit body, or other nonmetallic-sheathed cable termination.
- - - FPN: See 314.17(C) for support where nonmetallic boxes are used.
- - (B) Unsupported Cables. Nonmetallic-sheathed cable shall be permitted to be unsupported where the cable:
- - - (1) Is fished between access points through concealed spaces in finished buildings or structures and supporting is impracticable.
- - - (2) Is not more than 1.4 m (4½ ft) from the last point of cable support to the point of connection to a luminaire or other piece of electrical equipment and the cable and point of connection are within an accessible ceiling.
- - (C) Wiring Device Without a Separate Outlet Box. A wiring device identified for the use, without a separate outlet box, and incorporating an integral cable clamp shall be permitted where the cable is secured in place at intervals not exceeding 1.4 m (4½ ft) and within 300 mm (12 in.) from the wiring device wall opening, and there shall be at least a 300 mm (12 in.) loop of unbroken cable or 150 mm (6 in.) of a cable end available on the interior side of the finished wall to permit replacement.

Jim Port
05-28-2010, 04:59 PM
Darn Jerry, you missed the simplest one. NM is not for use outside.

There would also be issues if this were type UF cable too.

Jerry Peck
05-28-2010, 05:16 PM
Darn Jerry, you missed the simplest one. NM is not for use outside.

Jim,

Nope.

He covered that here:

If this Romex is rated for UV exposure,

If it is NM cable which "is rated for UV exposure", then what it is?
- Why, it would be UF, of course. :p


There would also be issues if this were type UF cable too.

That's why I posted the NM supporting and securing section ... :p ... because that is what the UF section refers to ... :D

'Supporting and securing' "UF" is not really a problem, is it? After all, it is "Underground" "Feeder", and when it is installed underground, it is "supported and secured" pretty dang well. :D

:cool:

mathew stouffer
05-28-2010, 06:14 PM
Here is a close up of the cable. What specific type of cable is this, I know it NM, but it seems to be a little difference.

Jerry Peck
05-28-2010, 06:20 PM
What specific type of cable is this,


Probably UF (Underground Feeder), it is sunlight resistant as well as being suitable for direct burial. It is not, however, intended to be strung from building to building as an aerial cable.

A messenger (supporting) cable could be run between the two building and the UF then properly supported and secured from it. Not sure it meets minimum height above ground (12 feet), though.

mathew stouffer
05-28-2010, 08:11 PM
Jerry, this is over a back yard, I thought the clearance was 10ft.

Jerry Peck
05-28-2010, 08:30 PM
Jerry, this is over a back yard, I thought the clearance was 10ft.

*IF* that yard is "only accessible to pedestrians" AND "with a grounded bare messenger", yes, 10 feet, because it would meet (1) below.

Otherwise, *IF* there is any opening to get any type of equipment or vehicle back there OR *IF* there is no bare ground messenger supporting it, then 12 feet, because it would not meet (1) below, it would meet (2) below.

(bold and underlining are mine)
- 230.24 Clearances.
- - Service-drop conductors shall not be readily accessible and shall comply with 230.24(A) through (D) for services not over 600 volts, nominal.
- - - (B) Vertical Clearance for Service-Drop Conductors. Service-drop conductors, where not in excess of 600 volts, nominal, shall have the following minimum clearance from final grade:
- - - - (1) 3.0 m (10 ft) — at the electrical service entrance to buildings, also at the lowest point of the drip loop of the building electrical entrance, and above areas or sidewalks accessible only to pedestrians, measured from final grade or other accessible surface only for service-drop cables supported on and cabled together with a grounded bare messenger where the voltage does not exceed 150 volts to ground
- - - - (2) 3.7 m (12 ft) — over residential property and driveways, and those commercial areas not subject to truck traffic where the voltage does not exceed 300 volts to ground
- - - - (3) 4.5 m (15 ft) — for those areas listed in the 3.7-m (12-ft) classification where the voltage exceeds 300 volts to ground
- - - - (4) 5.5 m (18 ft) — over public streets, alleys, roads, parking areas subject to truck traffic, driveways on other than residential property, and other land such as cultivated, grazing, forest, and orchard

Roger Hankey
05-28-2010, 09:01 PM
I could not endorse the use of UF or NM for this application even if properly supported, etc. since I have seen cables that were strung like this which had much of the jacket chewed off by squirrels.

Jerry Peck
05-28-2010, 09:05 PM
I could not endorse the use of UF or NM for this application even if properly supported, etc. since I have seen cables that were strung like this which had much of the jacket chewed off by squirrels.

Not sure anyone here is "endorsing it", only stating what would be "allowed" by "minimum" code.

There are a lot of things we see which meet minimum safety standards (i.e., "codes") but which we would not "endorse" as good practice.

Ken Amelin
05-29-2010, 05:49 AM
From what I read above, if you add a steel cable to that span and supported the wire every 4-1/2 feet then it would be acceptable?

ken horak
05-29-2010, 06:49 AM
Jerry-
You are referencing the incorrect code article.
Your post references artice 230.24. Article 230 is for services. This installation is a feeder. The difference is the voltage restrictions in respect to the minimum height requirement

NEC article 100 definition of service:

Service. The conductors and equipment for delivering electric energy from the serving utility to the wiring system of the premises served.


Article 225 Outside branch Circuits and Feeders is the article to use for this installation

225.1 Scope.

This article covers requirements for outside branch circuits and feeders run on or between buildings, structures, or poles on the premises; and electrical equipment and wiring

225.18 Clearance for Overhead Conductors and Cables.

Overhead spans of open conductors and open multiconductor cables of not over 600 volts, nominal, shall have a clearance of not less than the following:

(1) 3.0 m (10 ft) — above finished grade, sidewalks, or from any platform or projection from which they might be reached where the voltage does not exceed 150 volts to ground and accessible to pedestrians only

(2) 3.7 m (12 ft) — over residential property and driveways, and those commercial areas not subject to truck traffic where the voltage does not exceed 300 volts to ground

(3) 4.5 m (15 ft) — for those areas listed in the 3.7-m (12-ft) classification where the voltage exceeds 300 volts to ground

(4) 5.5 m (18 ft) — over public streets, alleys, roads, parking areas subject to truck traffic,driveways,on other then residential property,and other land traversed by vehicles, such as cultivated,grazing,forest, and orchard.

SO:
If that UF cable is only supplies 120 volts and only accessible to pedestrians then 10' is OK. If it provides 240 volt then it must be 12'

Whats the difference ? the difference is that under article 230 ( services) the 10' height is restricted to 300 volts, and under Article 225 the 10' height is restricted to 150 volts or less !

Scott Patterson
05-29-2010, 07:35 AM
Let's not overlook the improper installation of the the light fixture on the soffit..... :)

Corn Walker
05-30-2010, 06:38 AM
You guys are making a mountain out of a molehill. It's obvious to anyone with half a wit that you just need to zip-tie that cable to the swing set and you'll have corrected the support issue.

Vernon Sanders
05-31-2010, 11:31 AM
Here is a close up of the cable. What specific type of cable is this, I know it NM, but it seems to be a little difference.

The real question is how the wiring is comming out of the box for the light fixture, this probably should have been in EMT conduit and the box in the soffit should have a extension on it to properly secure the wiring method to it.

Scott Patterson
05-31-2010, 02:48 PM
The real question is how the wiring is comming out of the box for the light fixture, this probably should have been in EMT conduit and the box in the soffit should have a extension on it to properly secure the wiring method to it.

I'm betting that you will not find a junction box in that soffit.....

Rolland Pruner
05-31-2010, 04:13 PM
Hey also it looks like metal siding?? could be another problem

Jerry Peck
05-31-2010, 07:18 PM
Ken,

I will add highlighting to show you where the difference is that I am pointing out - my highlight hing will be larger size, bold and underlined as you have already used red and blue text:


Jerry-
You are referencing the incorrect code article.
Your post references artice 230.24. Article 230 is for services. This installation is a feeder. The difference is the voltage restrictions in respect to the minimum height requirement

NEC article 100 definition of service:

Service. The conductors and equipment for delivering electric energy from the serving utility to the wiring system of the premises served.


Article 225 Outside branch Circuits and Feeders is the article to use for this installation

225.1 Scope.

This article covers requirements for outside branch circuits and feeders run on or between buildings, structures, or poles on the premises; and electrical equipment and wiring

225.18 Clearance for Overhead Conductors and Cables.

Overhead spans of open conductors and open multiconductor cables of not over 600 volts, nominal, shall have a clearance of not less than the following:

(1) 3.0 m (10 ft) — above finished grade, sidewalks, or from any platform or projection from which they might be reached where the voltage does not exceed 150 volts to ground and accessible to pedestrians only

(2) 3.7 m (12 ft) — over residential property and driveways, and those commercial areas not subject to truck traffic where the voltage does not exceed 300 volts to ground

(3) 4.5 m (15 ft) — for those areas listed in the 3.7-m (12-ft) classification where the voltage exceeds 300 volts to ground

(4) 5.5 m (18 ft) — over public streets, alleys, roads, parking areas subject to truck traffic,driveways,on other then residential property,and other land traversed by vehicles, such as cultivated,grazing,forest, and orchard.

SO:
If that UF cable is only supplies 120 volts and only accessible to pedestrians then 10' is OK. If it provides 240 volt then it must be 12'

Whats the difference ? the difference is that under article 230 ( services) the 10' height is restricted to 300 volts, and under Article 225 the 10' height is restricted to 150 volts or less !

Ken,

Yes, I did reference the wrong section, HOWEVER ... the clearances are THE SAME in both sections and the voltage limitations are the SAME too.



SO:
If that UF cable is only supplies 120 volts and only accessible to pedestrians then 10' is OK. If it provides 240 volt then it must be 12'

The first part is correct, just as my first part was correct - "only accessible to pedestrians" is what I said, and you confirmed it, the two codes sections have the same height requirements as, whether or not it is service or feeders, it is the voltage to ground which matters and "only accessible to pedestrians" which clarifies it.

Thus, as I said (even though I used the incorrect code reference, the code reference you posted supports the same height clearances) *IF* the area is accessible to ... how did I say it? NOTE that I have deleted the part about "with grounded bare messenger" as that applies to services.

*IF* that yard is "only accessible to pedestrians" ... , yes, 10 feet,

Otherwise, *IF* there is any opening to get any type of equipment or vehicle back there ..., then 12 feet,

Those two requirements affect the minimum height clearance above grade REGARDLESS of which section section is applied.


Whats the difference ? the difference is that under article 230 ( services) the 10' height is restricted to 300 volts, and under Article 225 the 10' height is restricted to 150 volts or less !

Nope - BOTH sections have THE SAME voltage restrictions.

ken horak
06-01-2010, 10:29 AM
Jerry-
We were both on the correct path except on of us was looking at an outside branch circuit and one was looking at "service drop conductors"

service drop conductors are also required to be supported on and cabled together with a grounded bare messenger where the voltage does not exceed 150 volts to ground.
Outside branch circuit conductors do not have this requirement.

Jerry Peck
06-01-2010, 03:49 PM
Jerry-
We were both on the correct path except on of us was looking at an outside branch circuit and one was looking at "service drop conductors"

service drop conductors are also required to be supported on and cabled together with a grounded bare messenger where the voltage does not exceed 150 volts to ground.
Outside branch circuit conductors do not have this requirement.

And one of us stated, among other things:


SO:
If that UF cable is only supplies 120 volts and only accessible to pedestrians then 10' is OK. If it provides 240 volt then it must be 12'

Which was incorrect, and ...


Whats the difference ? the difference is that under article 230 ( services) the 10' height is restricted to 300 volts, and under Article 225 the 10' height is restricted to 150 volts or less !

Which was also incorrect.

While the other one of us used (and acknowledged the error) the incorrect code section, which did not affect the height requirements of which we are discussing. :)

bob smit
06-03-2010, 12:01 PM
Inspected a Homeowner job yesterday who would agree this is perfectly OK as long as the cables are out of reach of children.
Bob Smit, County EI

Jerry Peck
06-03-2010, 03:11 PM
Inspected a Homeowner job yesterday who would agree this is perfectly OK as long as the cables are out of reach of children.
Bob Smit, County EI

Heck, to make that cable useful ... ;) ... it needs to be low enough to use double duty as a clothesline. :D