#14 or #12 awg/residential wiring

Status
Not open for further replies.

nizak

Senior Member
Do most contractors here who mainly do residential work use #14 for general purpose receps and lighting? Do some municipalities require #12 as the minimum regardless of what load it's serving?
 

iceworm

Curmudgeon still using printed IEEE Color Books
Location
North of the 65 parallel
Occupation
EE (Field - as little design as possible)
Do some municipalities require #12 as the minimum regardless of what load it's serving?

I don't wire houses, however, in conversation with an Anchorage AHJ rep (inspector), she told me the borough required #12.

ice
 

augie47

Moderator
Staff member
Location
Tennessee
Occupation
State Electrical Inspector (Retired)
There are definitely some jurisdictions that require a #12 minimum. Locally about 1/3 of the E/Cs use 14 except where 20 amp circuits are required, many follow post #3, #14 on lights and smokes and a few use #12 as a minimum..
 

nizak

Senior Member
One item that usually comes up in conversation is that lights blink when a high wattage device(vaccum motor starting) is turned on.Many times an A/C condenser will cause blinking on any circuit when it starts as it draws 5x its running ampacity. Is the vac that is plugged into a general purpose 15A bedroom circuit any worse because it's 14awg? I would think that the instantaneous 80amp spike on the #12awg feeding the condenser would be more concerning.In 20 years doing residential work, I can't recall going back to a job where overloading a 15A circuit was encountered. I have gone back where homeowners were trying to run a couple 12-1500W heaters and a de-humid in one room, probably would have the same result with a 20A circuit.
 

edlee

Senior Member
Do most contractors here who mainly do residential work use #14 for general purpose receps and lighting? Do some municipalities require #12 as the minimum regardless of what load it's serving?

I wire lights in particular (as opposed to "general lighting" which refers also to receptacle outlets) in 14. All those 3-ways and dimmers: it's a lot easier on box fill.
 
For troubleshooting & loading purposes, I install a 15amp/14 gauge circuit to each bedroom/room AFCI, unless there's a lot of lighting (for example master bedroom & Bath) where I will install (2) 15amp circuits for rec & lighting.

20amp/#12 where required (kitchen, laundry, bath)

Never had a callback for over loading

#14 is much easier to work with.
 

iceworm

Curmudgeon still using printed IEEE Color Books
Location
North of the 65 parallel
Occupation
EE (Field - as little design as possible)
... Is the vac that is plugged into a general purpose 15A bedroom circuit any worse because it's 14awg? .
I don't think so. Consider the case of a house system where the service consists of a small pole mount xfm, long small wires from the xfm to the house panel, all circuits in the house originate from the panel.

Any VD on the service xfm and conductors shows up on all panel circuits. The VD on the #14 to the vacuum only shows up on the vacuum. #12 wire to the vac won't help the dip at the panel.

ice
 

Ponchik

Senior Member
Location
CA
Occupation
Electronologist
#14 lights and smoke detectors.
#12 for receptacles throughout the house.
 

Canton

Senior Member
Location
Virginia
Occupation
Electrician
Old days: 12 for receptacles and 14 for indoor lighting.

New days: 14 anyplace allowed and 12 only where required.

I will second that......#14.....cheaper, and a lot easier to work with. I use it anywhere I can get away with it.....:)
 

Buck Parrish

Senior Member
Location
NC & IN
A 15 amp breaker could be considered safer. Most lamps, fans, stereos, appliances, etc... have cords that usually have 16 gauge wire.
 

fmtjfw

Senior Member
Please provide more information. I am not familiar with these applications.

I have several 250V 50Hz German appliances and tools. I change the plugs from Schuko to NEMA 6-15 (250V 15A) and put in 250V 15A receptacles in several places. Since the voltage drop percentage is ? for 250V versus 125V for the same load, I used #14.

My house also has resistance heating in the ceilings that runs on 250V. Most sections are 7A or so. Thus #14 for the same reason.
 

iwire

Moderator
Staff member
Location
Massachusetts
I have several 250V 50Hz German appliances and tools. I change the plugs from Schuko to NEMA 6-15 (250V 15A) and put in 250V 15A receptacles in several places.

Likely an NEC violation.

210.6 Branch-Circuit Voltage Limitations. The nominal
voltage of branch circuits shall not exceed the values permitted
by 210.6(A) through (E).

(A) Occupancy Limitation. In dwelling units and guest
rooms or guest suites of hotels, motels, and similar occupancies,
the voltage shall not exceed 120 volts, nominal, between
conductors that supply the terminals of the following:

(2) Cord-and-plug-connected loads 1440 volt-amperes,
nominal, or less or less than 1?4 hp
 

Fulthrotl

~Autocorrect is My Worst Enema.~
I will second that......#14.....cheaper, and a lot easier to work with. I use it anywhere I can get away with it.....:)

it's easier to lasso and work with, but it sucks when a customer wants to plug in a
larger load.... so i use #12 for all receptacles, and #14 for all lights, etc.

with LED lighting becoming commonplace, you can put an awful lot of 5 watt led's
on a single circuit.... most of them with the power supply only draw about 15 watts.
 

iwire

Moderator
Staff member
Location
Massachusetts
I run 10 AWG, no electrical reason, I do it for the bragging rights.It is just one size larger than the rest of you guys run so that makes me a better electrician then you all. *




























<*That is sarcasm folks, don't take things to serious:)>
 
it's easier to lasso and work with, but it sucks when a customer wants to plug in a
larger load.... so i use #12 for all receptacles, and #14 for all lights, etc.

with LED lighting becoming commonplace, you can put an awful lot of 5 watt led's
on a single circuit.... most of them with the power supply only draw about 15 watts.

What single appliance load would exceed the capacity of a 15amp circuit? Especially in a residential setting?

BTW: I typically install a 20 amp circuit in the garage, in case they use a compressor or table saw.
 

K8MHZ

Senior Member
Location
Michigan. It's a beautiful peninsula, I've looked
Occupation
Electrician
What single appliance load would exceed the capacity of a 15amp circuit? Especially in a residential setting?

BTW: I typically install a 20 amp circuit in the garage, in case they use a compressor or table saw.

Years ago I did a service call where a 15 amp breaker was tripping. The culprit turned out to be a hand held hair dryer that was over 2000 watts.

I couldn't believe that UL would list such a device, especially since it only had 15 amp plug on it. The 'repair' was to get a dryer that was under 15 amps or not use one at all.
 
Status
Not open for further replies.
Top