8' rule for Service disconnecting means

[ludonded]

I know that if you are more than 8' from service entrance to panelboard, a disconnecting means is required. Only problem im having is that i cannot find it in the NEC codebook. If anyone could help me out with a section number that would be awesome. I greatly appreciate it.

 

[iwire]

You can't find it as no such rule in the NEC exists.

Below is as close as you will get.

VI. Service Equipment ? Disconnecting Means

230.70 General. Means shall be provided to disconnect all conductors in a building or other structure from the service-entrance conductors.

(A) Location. The service disconnecting means shall be installed in accordance with 230.70(A)(1), (A)(2), and (A)(3).

(1) Readily Accessible Location. The service disconnect-ing means shall be installed at a readily accessible location either outside of a building or structure or inside nearest the point of entrance of the service conductors.

The 8' you remember is likely just what has been traditionally accepted in your area.

 

[mwm1752]

Sounds like a local code -- not NEC

 

[infinity]

As Bob stated the restriction is for the portion of the SEC's that are within the building. There is no limit to their length on the outside of the structure so even if local rule said 8' you would need to know where to begin your 8' measurement. Around here 8' within the structure will not fly.

 

[tom baker]

Washington is pretty generous with allowing 15ft of service raceway inside a building. But we only allow 8 wiring methods, EG rigid, intermediate, PVC, but no EMT...

 

[GoldDigger]

As Bob stated the restriction is for the portion of the SEC's that are within the building. There is no limit to their length on the outside of the structure so even if local rule said 8' you would need to know where to begin your 8' measurement. Around here 8' within the structure will not fly.

In most places, the length of wiring in a raceway underneath the building is counted as in the building, although length which is covered by the specified depth of concrete is not.

 

[darekelec]

In nyc it's 10' or covered in 2" of concrete encasement if longer.

 

[Wilg]

6 feet here. "Because that's what it's always been..."
One of the most misunderstood rules for our inspectors and contractors...We manage to complicate this one on a regular basis. We've been known to use dreaded "common sense" on some inspections.

 

[mwm1752]

As Bob stated the restriction is for the portion of the SEC's that are within the building. There is no limit to their length on the outside of the structure so even if local rule said 8' you would need to know where to begin your 8' measurement. Around here 8' within the structure will not fly.

230.32 Protection Against Damage.
Underground service-lateral conductors shall be protected against damage in accordance with 300.5. Service-lateral conductors entering a building shall be installed in accordance with 230.6 or protected by a raceway wiring method identified in 230.43.

Good or bad idea I do not see where there is a restrictive length inside the building using 230.43. IMO
230.6 refers to which circumstances in which the SEC is considered outside the building.
230.43 refers to when the SEC enters the building a protective cover is required per article.

 

[iwire]

230.32 Protection Against Damage.
Underground service-lateral conductors shall be protected against damage in accordance with 300.5. Service-lateral conductors entering a building shall be installed in accordance with 230.6 or protected by a raceway wiring method identified in 230.43.

Good or bad idea I do not see where there is a restrictive length inside the building using 230.43. IMO
230.6 refers to which circumstances in which the SEC is considered outside the building.
230.43 refers to when the SEC enters the building a protective cover is required per article.

Regardless of 230.43 230.71(A) limits the length inside the building.

When 230.6 is applied the conductors are considered 'outside' even if inside.

 

[mwm1752]

"230.71(A) limits the length inside the building."

Iwire
Will you interprete the lenght restriction.

230.71 Maximum Number of Disconnects
(A) General. The service disconnecting means for each service permitted by 230.2, or for each set of service entrance conductors permitted by 230.40, Exception No. 1, 3, 4, or 5, shall consist of not more than six switches or sets of circuit breakers, or a combination of not more than six switches and sets of circuit breakers, mounted in a single enclosure, in a group of separate enclosures, or in or on a switchboard. There shall be not more than six sets of disconnects per service grouped in any one location. For the purpose of this section, disconnecting means installed as part of listed equipment and used solely for the following shall not be considered a service disconnecting means:
(1) Power monitoring equipment
(2) Surge-protective device(s)
(3) Control circuit of the ground-fault protection system
(4) Power-operable service disconnecting means

 

[mwm1752]

If 230.43 can be in lieu of 230.6 can that mean the conductors are still outside the building with the protection of 230.43?

 

[mwm1752]

Code commentary
"No maximum distance between the point of entrance of service conductors to a readily accessible location for the installation of a service disconnecting means is specified by 230.71(A)."
I would suggest both you & the 2011NEC are refering to 230.70(A) & I would defer there is a limit to length but only to the readily accessible location.

 

[infinity]

In nyc it's 10' or covered in 2" of concrete encasement if longer.

Just curious, what type of installation has a 10' maximum? I've seen large (4000 amp) services with parallel conductors far exceeding 10'.

 

[iwire]

"230.71(A) limits the length inside the building."

Iwire
Will you interprete the lenght restriction.

Sorry that was supposed to be 230.70(A)(1).

230.70(A)(1) limits the length inside with the words "inside nearest the point of entrance of the service conductors."

 

[hurk27]

If 230.43 can be in lieu of 230.6 can that mean the conductors are still outside the building with the protection of 230.43?

230.6 gives you the 5 conditions where the service entrance conductors are considered outside the building, you can not apply 230.43 to this requirement:

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

(3) Where installed in any vault that meets the construction
requirements of Article 450, Part III

(4) Where installed in conduit and under not less than
450 mm (18in.) of earth beneath a building or other
structure

(5) Where installed in overhead service masts on the outside
surface of the building traveling through the eave
of that building to meet the requirements of 230.24

Here is the 2011 commentary to 230.70(A)(1) that explains that the distance is and has always been left up to the AHJ to determine.

No maximum distance between the point of entrance of service
conductors to a readily accessible location for the installation
of a service disconnecting means is specified by
230.71(A). The authority enforcing this Code or AHJ has the
responsibility for, and is charged with, making the decision on
how far inside the building the service-entrance conductors
are allowed to travel to the service disconnecting means. The
length of service-entrance conductors should be kept to a minimum
inside buildings, because power utilities provide limited
overcurrent protection. In the event of a fault, the service
conductors could ignite nearby combustible materials.
Some local jurisdictions have adopted 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. See also 230.6 and
Exhibit 230.15 for conductors considered to be outside a
building.See 404.8(A) for mounting-height restrictions for
switches and for circuit breakers used as switches.

Which also references 230.6

Personally with the understanding that service entrance conductors in almost all cases are not protected by a OCPD and that they will burn free, I would hope most will keep the distance as short as possible when entering a building with SEC's

 

[Fishspark]

I know that if you are more than 8' from service entrance to panelboard, a disconnecting means is required. Only problem im having is that i cannot find it in the NEC codebook. If anyone could help me out with a section number that would be awesome. I greatly appreciate it.

take a look at SPS316.230(3) your State code if that helps

 

[GoldDigger]

Personally with the understanding that service entrance conductors in almost all cases are not protected by a OCPD and that they will burn free, I would hope most will keep the distance as short as possible when entering a building with SEC's

I agree with you 100%, but that also makes me wonder why a simple switched disconnect that does not include OCPD seems to be commonly accepted as limiting the risk!
That would seem to argue that there is a sense of a greater risk in the SEC wiring types, independent of overcurrent protection (possibly because of the Code provision allowing "undersized" Service Entrance Conductors in some cases.)

 

[mwm1752]

"230.6 gives you the 5 conditions where the service entrance conductors are considered outside the building, you can not apply 230.43 to this requirement:"

While I do agree that SEC's inside a building should be kept to minimum distances, it is interesting how the code lets you apply 230.43 as wiring methods for SEC's within a building as they find the nearest readily accessible location. The AHJ has the last word in determining this location. I had a building in which allowing the service gear on the first level was not applicable and it was moved to the third level. I did in fact require the SEC to be protected as 230.6 in order to define its location as outside the building. The application of 230.43 could have been an option IMO.

 

[darekelec]

Just curious, what type of installation has a 10' maximum? I've seen large (4000 amp) services with parallel conductors far exceeding 10'.

10' was what my first boss did when building services and I stayed with that. 4000 Amp services got cabinets right at service entrance points. You are the eagle and I am the fish if I am mistaken.
How about POCOs? Do they have any word on that?