Questions tagged [nec]

For questions about the National Electrical Code, NFPA 70. Just about all US jurisdictions that have adopted an electrical code use the NEC, often with a handful of local or state level amendments.

Filter by
Sorted by
Tagged with
2
votes
1answer
85 views

50 Amp Outlet Disconnect Requirements

My county uses the 2014 NEC with no modifications. I'm wiring my newly built detached garage myself. I had the rough-in inspection, and everything was ok for it, but the inspector had some concerns ...
1
vote
2answers
61 views

Is AFCI a requirement outside the United States?

I have been asked to come into a site (outside of United States; Central America to be specific) - but one of the personnel there asked about NEC compliance; specifically AFCI. How can I educate ...
1
vote
3answers
64 views

Using steel conduit as a ground intermitantly. Any problems with this?

Small back story: This is a Philly row home, so the long wall are solid brick. original outlets were non-existant or embedded in baseboards. While most of the home is being wired with romex, I am ...
0
votes
1answer
44 views

Can I notch the end of a piece of fire blocking to accommodate a wire?

I'm framing a partition wall and a lowered ceiling on one side of that wall. The space above the new, lower ceiling will essentially be attic space, so the inspector said I need fire blocking in the ...
3
votes
2answers
41 views

Do breaker trip curves ever begin BEFORE the load printed on the breaker handle?

It's commonly accepted that the continuous load of a circuit should usually not be more than 80% of the rating of the lowest ampacity link in that circuit. Do breakers ever 'enforce' this de-rating ...
3
votes
2answers
84 views

Abandoning wire in attic space

I'm in the US, and I have three recessed lights daisy-chained from a switch, and I want to take the last one (#3) out of service. I'm lowering the ceiling in this area, so converting it to a junction ...
1
vote
1answer
65 views

Can I run two 6/3 NM cables up the same 2x4?

I have two 6/3NM cables coming from the attached garage ceiling into a subpanel mounted low inside an exterior wall. One of the studs is occupied by A/C pipes so I'm hoping there's a way to get both ...
0
votes
1answer
50 views

In which spaces can small-appliance branch circuits have “No Other Outlets”?

Goal: Understanding the NEC code language for practical DIY application. All occurrences of the phrase "no other outlets" related to a house (not an RV) in the NEC 2017 are: 210.11 Branch Circuits ...
4
votes
1answer
367 views

How is “continuous wiring” defined in context of the 2017 NEC code?

First, some context: About AFCI protection in Dwelling Units, NEC 2017: 210.12(A) All 120-volt, single-phase, 15- and 20-ampere branch circuits supplying outlets or devices installed [...] shall be ...
3
votes
2answers
113 views

Back-to-back conduit bodies for wall transition

I am running an 80A (4AWG Copper) line for EV charging in my garage. I am using EMT conduit and I need to transition through drywall. Since the studs are not deep enough (2x4) for the minimum radius ...
2
votes
1answer
73 views

Will a SimpliSafe security system which include smoke detectors qualify under fire panel exception for the NEC's AFCI requirements?

To expand on the question I'm trying to put these AFCI's and GFI's everywhere I need them, but nowhere I do not. Also my experience with AFCI's up to this point have been poor. They trip when the ...
2
votes
3answers
510 views

Dual GFCI/AFCI breaker to support regular TRR USB outlets on kitchen counter: to code?

I would like to replace some outlets that run along my kitchen countertop because the TRR plugs are hard to plug in, and I would like to put ones that have USB jacks. I know that GFCIs are required ...
7
votes
4answers
1k views

How do you comply with NEC receptacle requirements in row homes with brick walls?

I'm rewiring a Philadelphia row home, which like many others, has brick and cinder block for the side walls. There is no framing, just lath and plaster. I know some flippers will put in 2x3 studs to ...
6
votes
5answers
4k views

Why do unfinished basements need GFCI outlets?

I was replacing outlets in the basement and noticed that unfinished basements require them to be GFCI protected. While I did do this, I can't help but wonder: WHY?? I searched for the NEC ...
3
votes
2answers
119 views

What is the maximum voltage you can have on exposed rails?

In this question, someone has a desk lamp with power totally exposed on metal parts. You also have installed overhead lighting on open rails doing the same thing. What does NEC say about the ...
3
votes
1answer
125 views

NEC Compliance: Removing a wall switch in favor of a remote for a ceiling fan

In my bedroom, there is a wall switch that controls a ceiling fan. I recently installed a wireless remote controller in the canopy of that ceiling fan so I could turn it on and off from the comfort of ...
1
vote
1answer
85 views

Do retrofit ground wires need to be run in conduit?

I'm moving my water heater to another corner of the room it is in, to allow for more usable space in the room. However, the grounding wire is only 14 ga instead of the required 10, and it's not in the ...
1
vote
2answers
122 views

2020 NEC code changes

OK, WOW, just reviewed the 2020 NEC changes scheduled to take effect this year. I'm asking if I'm interpreting the changes correctly: 1) Whole house surge protection. Required either between the ...
8
votes
3answers
975 views

Why aren't AFCI breakers required for bathrooms/lavatories?

Why doesn't NEC require AFCI breakers for bathrooms/lavatories? Is there a good reason NOT to install AFCI protection on a 15A/20A 120V bathroom outlet? (I.e., use GFCI only.)
1
vote
2answers
204 views

Does code allow for in-wall mounting of low voltage transformers?

I am asking if NEC code permits for in-wall (gang box) mounting of low-voltage transformers and power supples, and if so do these product have a name or term? My use case is low-voltage electronics ...
2
votes
2answers
90 views

Correct gauge and jacket type for feeder wire to subpanel?

I need to install a 200A panel about 100 feet from the meter base. I have 400A service coming to the building, broken out at the meter base into two 200A exterior disconnects. One disconnect is ...
2
votes
2answers
182 views

Does it violate US wiring code to have non-standard outlets?

Note: this is entirely theoretical. I have no (current) plans to actually do this. Would I violate any state/national building/electrical codes if I installed BS 1363 (UK plug/socket) sockets on a ...
13
votes
2answers
2k views

What range of heights are allowed for wall receptacles?

I need to mount a receptacle on a basement wall. If I can mount it high enough, it can go on the wood cripple wall instead of having to drill into the concrete and risk the excellent watertightness ...
2
votes
2answers
516 views

Why does NEC require circuit breaker locks only on hard-wired appliance circuits?

The National Electric Code (NEC) Section 422.30 requires "permanently connected appliances" to have "lockable" disconnects, so that power can be reliably cut to the appliance when it is serviced. ...
4
votes
2answers
696 views

Handybox Extension

Can you stack a handybox with an extension outside of the drywall? This puts the total box size at just shy for 4". I know handyboxes can be used with conduit, but can they be double-stacked in a ...
2
votes
2answers
757 views

How to wire up a 240 V oven?

I recently purchased a Whirlpool WOS51ES4ES electric oven from Home Depot with the intention of installing it myself. Our old oven is gas, so I need to run a new 240 circuit. The oven draws 20A. I ...
0
votes
3answers
72 views

Electrical Question for Receptacles in guest house

Wiring a out door shed that has everything that a home does; bathroom kitchen living room and extra bedroom. Pretty much like a guest home you can say. When I run my wire in the bathroom of it. The ...
1
vote
2answers
77 views

Solar 240 VAC source and load wires sharing a conduit

I'm planning on installing a new electric oven and solar panels on my house soon. Given the location of everything relative to my electrical service panel, both the panels and the oven will need to ...
2
votes
2answers
180 views

Exterior to Interior Wiring and Code Deficiencies?

I recently installed a 100a exterior subpanel adjacent to my main panel to allow for the installation of 240V and 120V service to a shed on the opposite side of my house, along with a 240V dryer of ...
4
votes
2answers
179 views

What are the legalities associated with mounting splicing wire connectors?

There are some situations, such as those involving large junction or pull boxes that serve as central takeoff points for many-plexed homeruns or homerun banks, enclosures that form central splice ...
0
votes
3answers
217 views

How to run 10/2 THHN outdoor wire in finished basement along ceiling?

I need a 220v (intermittent load will be 14 A max) single phase outlet about 30 feet from my distribution panel in my finished basement. The distribution panel is outside on the first floor. I do not ...
5
votes
1answer
262 views

Can I paint a load center cover?

I would like to paint the cover and door of my flush mount load center to match the wall color more closely. The manufacturer does offer a white in addition to the standard grey cover, but it is hard ...
-1
votes
1answer
79 views

In conduit with 75C wire, can I use #14 wire for 20A circuits?

I note that with 8 AWG wire... in NM-B (Romex) cable I can only get 40A: I am required to pull from the 60 degree C column of Table 310.15(B)(16). However, in conduit, with 75C wire (THHN) and ...
3
votes
1answer
83 views

1 generator + multiple ATSes: how can I install this to Code without unobtanium?

I want to supply standby power to both units in a separately metered duplex from a single permanently installed generator. The cheapest way to do this is a pair of bog-standard ATSes and a smallish ...
2
votes
0answers
49 views

How do I connect surface wireway to a breaker box?

I am running Legrand/Wiremold 4000 series for a garage shop. The instructions for the panel connector (4086A) consist of a tiny picture that implies all I need to do is cut a large square hole in my ...
7
votes
3answers
2k views

Any way to meet code with 40.7% or 40.44% conduit fill?

I’m running conduit along the walls in my shop (in a commercial warehouse) to provide power to some machines and additional outlets. The service is 3 phase, 208 V, 100 A. One of the machines requires ...
3
votes
4answers
870 views

Does this violate electrical code? (UF run plugged into GFCI to use smart outlet)

I built a deck on the back of my house last year and installed a new breaker and a handful of outdoor electrical outlets. I wanted one outdoor outlet to be switchable via a smart outlet, but my smart ...
1
vote
1answer
336 views

Oven wiring - needing to add a ground, can I retrofit?

I'm dealing with a 1970-built home and the oven has 6-3 without ground running to the oven. 2 hots and the neutral. Got a new oven coming in and want to make sure it's wired right. I could run new ...
9
votes
4answers
2k views

Why are 120 V general receptacle circuits limited to 20 A?

The NFPA-70 (National Electrical Code) prohibits the use of breakers larger than 20 A for general receptacles. But I have my doubts. A 20 A breaker on a 120 V circuit with appropriately sized wires ...
1
vote
0answers
48 views

Dedicated 240v 30A Circuit Switched for A/C and NEMA 14-30 [duplicate]

I have a dedicated 240 volt circuit that's hard wired into my air conditioning unit. The circuit has a 30 amp breaker at the main box and another 30 amp breaker on the wall next to my air conditioner....
1
vote
2answers
109 views

IBT and whole house transfer switch

The inter-system bonding termination (IBT) is where other services like telephone and cable TV get their ground bonds from the house's grounding electrode system (ground rods). 2014 NEC (NJ) 250.94 ...
1
vote
1answer
56 views

Stacking 'Main lug' load centers for garage

I am aware of most NEC codes and am actually asking if this is allowed, There really shouldn't be any reason..I also fully understand keeping my netural and ground seperate and how the bus bars are ...
1
vote
2answers
189 views

Why don't we just use combination AFCI/GFCI breakers for every circuit in a home?

With pretty much every circuit in a home needing one of the two types of protection (AFCI or GFCI), why don't all new homes have combination breakers installed just to be safe? Would it hurt anything ...
1
vote
2answers
182 views

Romex exiting junction box just below 8 feet

I am installing new outlets by drilling up from the garage between the wall cavity and fishing romex up. As seen in the picture: I had my first inspection and the inspector called out that the ...
1
vote
3answers
87 views

Extremely low suspended ceilings? (NEC)

Here are the key points: Condo in NYC with concrete ceilings Recessed lighting "Exactly" The ceiling is to be dropped by only 2-1/2" The light in mind is a 1-1/4 LED light (Extremely low profile) Ex: ...
0
votes
2answers
917 views

Running a low-voltage audio cable through a wall; with or without conduit?

I'm running wire for a 70V audio system and there is a barrier wall in the way of my run. I was wondering if it is legal as far as NFPA 70 / NEC goes if I just poke a hole in the wall (non-insulated ...
3
votes
1answer
568 views

Derating 6 current-carrying conductors?

I'm having a hard time understanding 310.15(B)(2)(a). Here's the boat I'm in: I hooking up a tankless water heater that calls for 3 40 amp breakers (it's a 24 kw Ecosmart). So I put in a sub panel in ...
0
votes
3answers
277 views

Is “14 AWG” NM-B allowed by the newest NEC for new residential construction?

Is "14 AWG" NM-B allowed by the newest NEC for new residential construction? My concern is what the NEC says concerning 14 AWG NM-B for new residential construction. I have been told that the "NEC ...
3
votes
2answers
4k views

Can I wire a doorbell transformer in-wall this way?

My current under-powered doorbell transformer is in a very awkward location (old home, etc.) and in a location where several old wires are cable-nutted together and I would rather not replace it there....
1
vote
1answer
895 views

What does NEC require for strapping down conduit and wire here?

Below is a picture of the current conduit and wire setup for my new underground service into my house with generator automatic transfer switch and manual transfer switch to allow me to switch to an ...