Our Goal is FOR ALL STAKEHOLDERS TO
HAVE A SUCCESSFUL PROJECT with us
and that together we keep people and
structures safe and buildings
economically viable to serve the needs of
our community.
We strive for:
May 11th, 2016
EXCELLENT CUSTOMER SERVICE!
and
QUALITY INSPECTIONS!
OUR NEXT MEETING IS JUNE 8th
I. Customer Service Reminder, Mr. Rains
II. Consistency Questions
1)I have a neighborhood that Duke will not relocate lateral to the other
side of the lot, assuming they no longer want to pay them to, where the
garage is. EC has started running SER through the house from a main on
one side to the panel in the garage. It is a main power feeder per
310.15(B)(7). This being said I was recently told by another inspector
that they did not have to apply 338.10(B)(4) where in thermal
insulation. I had been having another EC in another neighborhood
derating the SER to 60° because 10' or 10% of it was in the insulation.
Does this not apply to main power feeders? If so, why not?
RAINS
338.10(B)(4) refers us to Part II of 334, excluding 334.80. Then it further
instructs us that in thermal insulation the ampacity shall be in
accordance with the 60-degree C rating.
310.15(B)(7) of the NCEC allows a diversity demand for the feeder
carrying the total load of the dwelling unit to use the table reducing the
allowable conductor size by load diversity, not adjusting for thermal
calculation.
2) When is it required to fill the nipple on a back to back service in a
single family dwelling?
HARTMAN
Per 300.7 of the code they should be sealed to prevent condensation
issues due to thermal transfer.
3) Are liquidtight connectors that are approved for wet locations OK for
direct burial?
DELLINGER
We would need to see the listing information from the manufacturer
and UL. Generally, no per UL.
4)I have a service trough with meters and mains below. I added a meter
and a main like all the existing equipment. The inspector turned me
down and said I would have to change the service so that ALL mains
were contiguous (even the existing mains)! Is this correct? SIMPSON
We did have an interpretation that led us to that but as of 3/29/16 it’s
not. Per Mr. Starling at NCDOI: I lean towards the idea that grouping of
disconnects is uniquely dependent of the structure it serves. The service
disconnects for the structure should be arranged in a manner that
allows someone to disconnect all the power from a building in one
general location. I would agree that there should be no reason that
other building components or systems should infringe on that area
where the disconnects are located. Section 110.26 (E)(2) helps the
inspectors keep this area free from other equipment that do not belong
in that special zone. However, meters, conduit, and other necessary
electrical equipment should not necessarily be prohibited to be installed
where they come between the handles of the disconnect.
5)I ran liquid tight flexible metallic conduit to join two sections of PVC
raceway for service conductors to a building. I was turned down
because there is no way to bond the flex. Does 250.80 exception not
apply? It seems like the intent is the same.
KING
NO, it only applies to a metal elbow.
6)What size breaker can I use to protect 12, fourteen gauge wires, ran in
a conduit to feed 15A general use receptacles?
WEST
240.4 (B) (1) would prohibit this. You could divide the conductors in to
multiple conduits to avoid this issue.
7)When performing Plan Review and Inspections on multi-occupancy
dwellings, what is the responsibility of the reviewer concerning the
individual units, and what is the responsibility of the inspector by CE
policy.
KALE
The review team is to only review to the unit panel as the rest takes too
much time and is very subject to field change. We look at the units as
individual residences that require no review. The inspector will cover all
system elements for code compliance.
8)Is there any guidelines as to the location of a utility tap box used in
conjunction with a utility transformer?
BARNES
The specs and location of the tap box would need to be identified for us
to know if building/electrical protection is needed.
9)How do we resolve the conflict between CE Policy and Duke Energy’s
Policy on transformer location and clearances?
RAINS
We will require what is needed to protect the building. Duke Energy
seems to be interested in other criteria. Their construction services
book advises their customers to check with the local AHJ. The criteria
we agreed to is still on our website.
10)When an elevator is required for a 5 story building to be used as a
means of egress, how do we know in the plan review stage whether it
requires Emergency Power (NEC 700) or Standby Power (NEC 701).
What system is required is specified by the NCBC. If the electrical
examiner is unsure of the appropriate call, I would suggest that the
building examiner provide that information to the electrical examiner by
email. If there appears to be a conflict, then the Building CA could
decide the issue.
HARTMAN
11)When the water line is part of the GEC system, does the water line
need to be connected at the street? If so, is this a CE SOP or is this per
CMUD?
DELLINGER
NEC 250.52(A)(1) states we can use a metal underground water pipe for
the grounding electrode. If it has no water in it is it a water pipe? It has
long been Meck. County CE’s interpretation that it has to be complete
to qualify. We have had two incidents of personnel injury when power
was connected without the water system being complete.
12) I have 2 buildings located 10 feet apart, on the same property and
same owner. Building A has the service and building B has a subpanel
fed from building A. Can I install 2 ground rods between them and use
them as the made electrodes for both?
SIMPSON
Per NEC 250.32 the grounding electrode(s) shall be installed. This
indicates that no duplicate use is allowed as posed in the question.
13) Does the low voltage data and voice cables installed underground in
conduit have to be listed for a wet location?
KING
Cables generally have to be used in accordance with their listing. 110.3
(B) and GS 66. Underground conduits are wet location and the cables
would need to be rated for wet locations. See communication circuits
800.47 which disagrees with GS. We don’t see how either way will
make a safety impact.
14) Can I install a NEMA 1 panel in a damp location (under a shelter
outside)?
WEST
Well yes you can but the inspector will need to turn it down. NEMA I is
for indoor locations and offers no protection from water penetration. If
the location of the panel is well within the structure so as to avoid direct
rain and dripping a NEMA 2 might could be used if inspector judged ok
and the location as indoors. Generally, a NEMA 3 would be needed.
15)In the service panel, do I have to land my EGC 's directly on the
neutral bar?
KALE
In general terms no. There is no potential difference in the bars of
grounded conductors and equipment grounding conductors at service if
they are bonded together. Be sure to follow manufacturer’s
installations instructions. If not bonded and the can is the only common
point, then EGCs are all that can land on the EGC bar.
16)We need to replace a 75 kva 480/208 transformer in our facility, do
we need to have this replacement permitted?
BARNES
Yes. No exception is allotted for permitting this work in 204.3 of the NC
Admin. Code or NCGS.
17)Can a 50-amp receptacle be fed by a 30-amp circuit breaker?
No. 210.21(B)(1) and 210.21(B)(3) prohibits this.
RAINS
18) Is there a limit on how many NM cables I can pull through a drilled
hole in a wooden stud?
HARTMAN
No limit is prescribed by code. The key is what will fit without damaging
the cable. Be aware of 334.80 derating requirements as well.
19) Can EMT be installed under or in a slab?
DELLINGER
Yes. See 358.10. Corrosion protection needs to be considered. Fittings
need to be listed for the purpose.
20) We have some pre-wired office furniture that came with isolated
ground receptacles. We did not provide an isolated ground with the
branch circuit. Can we tie both of the grounds to our branch circuit
ground? And do we have to change the isolated receptacles to nonisolated grounded receptacle?
SIMPSON
The provision for isolated grounding is just that. You can’t make a
hybrid system out of it. You must either choose to follow the required
grounding system as normal or choose the isolated system.
21)In the meter can shown in the picture below. I landed my GEC on the
lug and the inspector turned me down. Was he correct? I do this all the
time.
KING
It appears the can is being used to connect the GEC to the grounded
conductor. That is not allowed per NEC 250.24. If it is a supplemental
GEC it is allowed as shown.
22)We added some lighting in an existing open office area, all of our mc
cable and lights were supported and secured per the NEC, the inspector
turned my job down citing that existing defects were my responsibility
because we added wiring. He said if you alter the ceiling its yours even
though the defects had nothing to do with our scope of work. Is he
WEST
correct?
If the contractor’s scope of work meets the code, then an RQ needs to
be created and the owner advised to get violations corrected. If an
existing circuit or feeder is used it must be in compliance as well.
23)We changed out the 2x4 lay ins at an old office building, all we did
was disconnect and reconnect wires which were Romex. All Romex was
supported properly. Are we required to replace Romex with MC?
NO! Like for like replacement is allowed if it met the code at the time.
If other, then replacement to code occurs.
KALE
24)I was turned down for disposal not being installed with a receptacle
outlet installed under sink. We have been allowed in the past to leave a
cord and plug connected disposal out, as long as we provide outlet. Has
the policy changed?
BARNES
Our policy (6.2) for several years states the disposal must be set for
final.
25)I installed an outlet with a metal box in a media panel, the metal box
is attached to the media panel by machine threaded screws and the
metal box is properly bonded, so why would the inspector turn me
RAINS
down for not bonding the media panel?
In this case the grounding is fine unless the manufacturer’s instructions
state differently.
26)In looking at Duke Energy’s new Requirements for Electrical Service
and Meter Installation for NC and SC, what are Plan Reviews obligations
for documenting these changes on approved drawings? Specifically, in
regards to fig. 47A and 47D. Fig.47A indicates the meters and
disconnects be mounted over the service trough. Fig. 47D indicates
meters and disconnects mount below service trough when a C/L fuse
cabinet is mounted ahead of trough. Does plan review need this
documented on single line diagram prior to approval since this is a
utility provider requirement?
HARTMAN
We have no obligation to Duke’s standards.
27) I have a project in plan review that is a 4 story private school with
class rooms and administrative offices.
The NEC has changed has added an exception to 220.12 Lighting Loads
for Specified Occupancies.
The following exception to NEC 2014 220.12 reads:
Exception: Where the building is designed and constructed
to comply with an energy code adopted by the
local authority, the lighting load shall be permitted to be
calculated at the values specified in the energy code where
the following conditions are met:
(1) A power monitoring system is installed that will provide
continuous information regarding the total general
lighting load of the building.
(2) The power monitoring system will be set with alarm
values to alert the building owner or manager if the
lighting load exceeds the values set by the energy code.
(3) The demand factors specified in 220.42 are not applied
to the general lighting load.
We use the 2012 NC Energy Conservation Code as our required energy
code. 505.5.2 of the NCECC addresses the Building area method and
the space-by-space method to be calculated at 0.89 va. per sq.ft. NEC
220.12 requires 3 va. Per sq. ft. This is around 1/3 of the required load
of NEC 220.12.
(A) Other than checking that 220.42 are not applied, what requirement
will be needed at plan review to ensure the designer has a code
compliant design?
(B) Will this have any impact for the field inspector for verification of the
monitoring system and required alarms for this design?
DELLINGER
The designer needs to provide the calculation used if the exception is
used. The monitor and alarm system need to be shown as required
also.
28) The new Duke Energy manual requires the minimum trough size 14”
X 14”. The 2014 NEC 110.26 (A)(3) will be a problem for contactors. How
is this now being handled in the field by inspectors? Will our field
inspector’s approach this differently with Duke’s new trough size?
The contractor will have the responsibility to meet code appropriate
clearances and continue to bond all service equipment as required by
code.
SIMPSON
29) Can the light over the kitchen sink be on the same circuit as the
KING
disposal?
210.23 (A)(2) allows it if the disposal does not exceed 50% of the circuit.
30) Can a ground rod be installed in a building?
WEST
Code does not prohibit this.
31) Can MC cable be used in brick work?
KALE
See 330.10 & .12. MC is not to be embedded in mortar except in dry
locations. Stubbing thru an exterior wall is not an issue. Otherwise the
cable needs to be rated for the environment.
32) Can the GEC be spliced in panels on ground bars?
Yes, per 250.64(D)
BARNES
33) Is a detached building disconnect means to be service rated?
RAINS
Maybe. See 225.36 and 250.32
34) When using metallic flex between a 480V to 120/208V transformer
to a 120/208V panel, is it necessary to bond the flex with bond bushings
or bonding locknuts?
No. See NCEC 250.30 and the following.
Review of
2014 Residential Changes