# Basic Residential Wiring



## a'ightthen (Mar 17, 2012)

Well a'ightthen, been stewing on this for a bit.

Instead of getting involved in heated discussions over right vs wrong, why not lay out the basics?

Disclaimer is that all posts are the opinion of the poster and, not having distinctive experience of your local AHD ( Authority Having Jurisdiction), are simply offered as opinion via experience in the hope of being of assistance. All information provided is opinion only and should not be considered safe nor acceptable in your personal application.

Ye should seek a local, competent provider of services for a safe and compliant installation.

In other words, we are trying to help but accept no personal liability in doing so ... ye should know what you are doing or hire someone that does and accept the responsibilities of doing so.

Just pondering a place for advice that is added by ones personal experience without being considered as the facts/law in your locale - seek local help

Thoughts being such as ....










I consider this to be a NEMA ( National Electrical Manufacturers Association) 5-15R. The 5 being associated with 120 volts AC, the 15 being the amperage rating and the R being a receptacle ( vs a P ( plug)).

Some things to note ... the right side slot ( Hot, L1) is shorter than the left ( Neutral, L2). This came about as a means to prevent appliances from having them crossed ... such that power ran throughout the appliance to the wrong end of the switch meant to prevent this situation. Power is meant to enter the appliance and be "stopped" by the power on switch ... without this orientation, it was possible to open an appliance and get shocked due to the plug being inverted ) prior to the addition of the ground prong.

Notice that the color of the screw terminals are different on this particular receptacle ... bronze/brass ( right side) color being for the "hot" and silver/white color being the "neutral".

I am of the opinion that this device is to be "counted" as 180 watts of the total circuit. If this is so, a 20 amp circuit loaded to 80% would allow but 10 of these on the 20 amp circuit.

The green screw is for the ground. It is internally bonded to the yoke ( means for mounting via screws).

It's a chunk of info for what most consider "simple" but this is my opinion 

So who wants to explain 3&4 ways? LOL


----------



## farmrbrown (Jun 25, 2012)

a'ightthen said:


> So who wants to explain 3&4 ways? LOL


Explain'em?
I try not to even _mention_ them, lol.


----------



## Nimrod (Jun 8, 2010)

http://users.wfu.edu/matthews/courses/p230/switches/SwitchesTut.html


----------



## watcher (Sep 4, 2006)

You forgot to get into the "does the ground hole go on top or bottom" debate.


----------



## ace admirer (Oct 5, 2005)

it is suggested that ground go up ("upsidedown") it is not a rule as of 2011 nec

"three way" is a single pole double throw switch, "4 way" is a type of double pole-double throw switch. can anyone give the history of why they are called 3 way or 4 way? i would like to know.

5 recpt. on 15 amp circuit, 8 recpt on 20 amp circuit


----------



## TNHermit (Jul 14, 2005)

Nimrod said:


> http://users.wfu.edu/matthews/courses/p230/switches/SwitchesTut.html


Thanks
About to wire up my first three and four ways in the TIny House. I think I can follow that


----------



## MushCreek (Jan 7, 2008)

You better not put any of the outlets pictured on a 20 amp circuit. That's a 15A outlet. It's also not tamper-resistant, which was added by NEC in 2008. While we're at it, nearly every circuit that isn't GFI needs to be AFI, a pain, since many motors, such as your vacuum cleaner will trip an AFI. NEC doesn't actually specify how many outlets can go on a circuit, although 180 watts per outlet is a good way to figure it.

I'm in the middle of wiring our new place, and there's a lot to it. At least electrical code is specific and clear-cut. Plumbing, on the other hand, is quite vague. I have 3 different plumbing books, and each one has conflicting information. If I could figure out which book was 'right', I'd burn the other two!


----------



## wharton (Oct 9, 2011)

Mushcreek, unless there has been a very recent code revision, 15 amp devices (both switches and receptacles) are acceptable on a 20 amp circuit. I have found that the arc fault issue with vacuums and such is a pretty limited issue. I know that the problem exists, but I never heard from one of my customers who had the issue. I agree that the 180 watt calculation is better that the current requirement. Currently there is a prescribed "watts per sq. ft" requirement for convenience outlets in bedrooms, and other living areas. It's way too lax, as it allows (IIRC) for a single 15 amp branch circuit to cover 500 sq. ft of floor space. Than said, the comment about five outlets on a 15 amp breaker is a little too conservative, in many cases you wouldn't even cover a whole bedroom, or other modest sized room with five outlets. This not only would get awfully expensive, since an arc fault breaker runs $40, but you would then have a room with convenience outlets served by two separate circuits, which could be needlessly confusing. 

As for the right plumbing book, you need a book called "Code-Check" plumbing. It covers both plumbing codes IRC & UPC in great detail, and it's cheap and very easy to understand. One of the bigger enforcement agencies in the region recommends the whole code check series to any builder or tradesman, and they also defer to it, if there is a disagreement. 

As for the ground up question, I started doing it decades ago, when it became a specification requirement in places like schools and hospitals. This was due to it theoretically being safer, when and if, the unlikely combination of a metal cover plate comes loose and falls across the prongs of a cord end that is only partially plugged in. Think real long and hard before you wire a house and put all the outlets upside down. Fact is it's a real PITA when actually using it in the real world. A lot of non-standard cords are specifically designed to be used ground down. In particular portable air conditioners and hair dryers with cord end GFCI devices, and right angle plugs found on everything from refrigerators and power strips. IMHO, there is no compelling reason to do it in a residential application with plastic cover plates, and you will end up regretting it.


----------



## a'ightthen (Mar 17, 2012)

Very good points on the tamper resistant and AFIs MushCreek.

15A devices on a 20A circuit is fine .... 210.21(B)(3). As long as it is not a single receptacle on an individual circuit ( 210.21(B)(1)).

Since a 20A 5-20P will not fit into the 5-15R, the 15A rating is considered safe ... but we have all seen the extension cord nightmares. Other side being that you can not put a 20A outlet on a 15A circuit.

Agree that there is no limit defined on the number of receptacles allowed on a residential installation. Even the 3 watts/sq ft deals with service calculations. Excluding the SABC, Appliance and other mandated circuits, one could actually place most of the house on a single circuit - they really should address this.


----------



## farmrbrown (Jun 25, 2012)

a'ightthen said:


> Very good points on the tamper resistant and AFIs MushCreek.
> 
> 15A devices on a 20A circuit is fine .... 210.21(B)(3). As long as it is not a single receptacle on an individual circuit ( 210.21(B)(1)).
> 
> Since a 20A 5-20P will not fit into the 5-15R, the 15A rating is considered safe ... but we have all seen the extension cord nightmares. Other side being that you can not put a 20A outlet on a 15A circuit.


Very true.





a'ightthen said:


> Agree that there is no limit defined on the number of receptacles allowed on a residential installation. Even the 3 watts/sq ft deals with service calculations. Excluding the SABC, Appliance and other mandated circuits, one could actually place most of the house on a single circuit - they really should address this.


And if I hadn't seen it myself before, I'd swear you must be joking, LOL.
I haven't actually seen the entire house on one circuit, just more than half of it.:hammer:
"Oh, I just want to add a light in the kitchen......."


----------



## TNHermit (Jul 14, 2005)

Just a suggestion . If your going to lay out the basics you might want to explain some of the nomencalture like 20A 5-20P 5-115 R and such


----------



## farmrbrown (Jun 25, 2012)

Fancy talk for those new-fangled outlets and plugs, the ones with one side bigger than the other or turned to the side.

http://customavrack.com/products/993-nema-5-20p-plug-adapters.aspx


----------



## ||Downhome|| (Jan 12, 2009)

never understood why a 3-way is called a 3-way when a 4-way should be a 3-way...
would not mind some one explaining that...
but they both have a "common" 

so any one care to share?


----------



## wharton (Oct 9, 2011)

a'ightthen said:


> Very good points on the tamper resistant and AFIs MushCreek.
> 
> 15A devices on a 20A circuit is fine .... 210.21(B)(3). As long as it is not a single receptacle on an individual circuit ( 210.21(B)(1)).
> 
> ...


Probably best to end all the talk of NEMA specs. and numerical designations regarding outlets and plugs. It adds needless confusion to the conversation, and unless I am ordering a plug or outlet for something specific like a generator, or welder, it really doesn't come up when doing this stuff full time. Your comment about extension cord nightmares is a little vague, I assume it refers to a lack of convenience outlets in an installation? As for 20 Amp plugs in general. With nearly thirty years in the trade I have never seen one show up in a residential setting, and have only encountered a handful on very heavy cord connected industrial grade tools. Usually they last a week until somebody gets tired of not being able to plug them in, and they get cut off and replaced.


----------



## Raymond James (Apr 15, 2013)

I do not know codes . I know if I put in a 15 amp breaker I used 15 amp wire, switches and outlets. I did the lighting fixtures with 15. I ran 20 amp breaker 20 amp wire , switches and breaker to the outlets. I did two 20 amp lines to the kitchen and I did dedicated lines to the stove , the hot tub, the freezer, and a couple ac outlets. I used ground fault breakers on any circuit close to water so bathrooms, kitchen and laundry . 

I put the ground outlets up thus I now have three very short extension cords in use. I thought about cutting cords and replacing plugs but decided to go with the extensions. I wish I had read this posting about 12 years ago.


----------



## TNHermit (Jul 14, 2005)

Here is a question for someone In a house you ground the box to a rod outside. My TH is on a trailer. With a very metal frame  SO what do you do in that case or I suppose in an RV as they are on rubber tires. Although the TH sets on metal jack when parked. Do you just ground to the frame.?


----------



## wharton (Oct 9, 2011)

In the case of a stationary RV or trailer, supplied by a pole mounted "trailer service" I would do the all the normal grounding, which current requires TWO rods driven 8' apart. Then I would drill the frame, install a lug and run a "Bond wire" of #6 bare solid from the frame to the service, connecting it to the ground bar in the service panel, or using a "split-bolt" to attach it to the main ground wire. Oddly enough, you are not grounding the trailer frame, but bonding it. This is to assure that the frame, and the incoming electrical service have a ground value at a common potential. This is the same reason that you bond gas piping and metallic water piping. Even though it sounds a little "out there", difference of ground potential is a often ignored and misunderstood. Personally, I have been knocked on my butt when I got caught between two different grounds, and it can be fatal. If you want to see an extreme case of this, look up proper procedures for properly bonding everything involved with a steel reinforced, concrete in-ground pool installation. It is a complicated, but critical part of building one.


----------



## TNHermit (Jul 14, 2005)

wharton said:


> In the case of a stationary RV or trailer, supplied by a pole mounted "trailer service" I would do the all the normal grounding, which current requires TWO rods driven 8' apart. Then I would drill the frame, install a lug and run a "Bond wire" of #6 bare solid from the frame to the service, connecting it to the ground bar in the service panel, or using a "split-bolt" to attach it to the main ground wire. Oddly enough, you are not grounding the trailer frame, but bonding it. This is to assure that the frame, and the incoming electrical service have a ground value at a common potential. This is the same reason that you bond gas piping and metallic water piping. Even though it sounds a little "out there", difference of ground potential is a often ignored and misunderstood. Personally, I have been knocked on my butt when I got caught between two different grounds, and it can be fatal. If you want to see an extreme case of this, look up proper procedures for properly bonding everything involved with a steel reinforced, concrete in-ground pool installation. It is a complicated, but critical part of building one.


Sounds good but i dnot think that's the norm as you move from site to site. Seems like there is something a little simpler that could be done. TH's probably don't move as often as a regular RV. Although I have read of a guy that moves every couple weeks


----------



## MushCreek (Jan 7, 2008)

Thanks for the info on a 15A on a 20A circuit- obviously, I'm no electrician!

The latest trend in residential electrical devices is that wattages are actually going down, versus having gone up since electricity was first used. I'm using all LED lights, at less than 10 watts a piece as opposed to 75 watts or so for incandescent. I am calculating my lighting circuits based on incandescent loads, however, as I have no way of knowing what a future owner might do. I imagine that by the time I'm out of this house, incandescent lights will be a quaint memory, but you never know.

I'm wiring all of my outlets on 20A circuits, with a maximum of 6 outlets per circuit. My current home is all 15A, with as many as 10 outlets on a circuit, and I've never popped a breaker unless the device was actually faulty, but I like everything heavy-duty. You never know when you're going to want to run an air compressor in the living room!


----------



## wharton (Oct 9, 2011)

TNHermit said:


> Sounds good but i dnot think that's the norm as you move from site to site. Seems like there is something a little simpler that could be done. TH's probably don't move as often as a regular RV. Although I have read of a guy that moves every couple weeks


You are correct it isn't standard procedure when it comes to RVs or any manufactured building that moves frequently. There are many ways to do it, the key however is to not establish a separate ground, that is not bonded to the ground that is part of the power supply.


----------



## a'ightthen (Mar 17, 2012)

wharton said:


> Probably best to end all the talk of NEMA specs. and numerical designations regarding outlets and plugs. It adds needless confusion to the conversation, and unless I am ordering a plug or outlet for something specific like a generator, or welder, it really doesn't come up when doing this stuff full time. Your comment about extension cord nightmares is a little vague, I assume it refers to a lack of convenience outlets in an installation? As for 20 Amp plugs in general. With nearly thirty years in the trade I have never seen one show up in a residential setting, and have only encountered a handful on very heavy cord connected industrial grade tools. Usually they last a week until somebody gets tired of not being able to plug them in, and they get cut off and replaced.


 Correct, drop cord comment revolves around the #16 extension cords with 6 "plugs" and the ground cut off so they will fit. All we can do is provide the end user with a system that we believe to work ... can not control what happens after that.

The NEMA #s, I tried to explain a bit in the OP but consider relevant when comparing for clarity. Confusion is added by the lack of consistency and the differences of "local".

Here, I would ask for a single 6-20R where as others may ask for a 230 volt, 20 amp single receptacle for an AC.

I might say that they can put the material in the F350 crew cab dually .... others might say the ford pickup with 4 doors and 4 wheels on the back.

Each is true.

Different areas, different terminology.

I can not remember if school started in August or September .... but this is my 32nd year of this game and I've seen more than I ever cared to. Many a day has existed when I wished that I knew nothing for the times that I helped others instead of spending time with my family ... know that ye have felt that.


----------



## hornetd (Nov 1, 2011)

TNHermit said:


> Here is a question for someone In a house you ground the box to a rod outside. My TH is on a trailer. With a very metal frame  SO what do you do in that case or I suppose in an RV as they are on rubber tires. Although the TH sets on metal jack when parked. Do you just ground to the frame.?


Since you seem to be asking about a trailer home that will be moved rather frequently the usual methodology is to wire a four wire flexible cord to the trailer's electric panel. That panel may or may not be wired as a Service Disconnecting Means. (On an actual travel trailer it would never be wired as the service disconnecting means.) Under the National Electric Code it can only be wired as the Service Disconnecting Means if it was installed by the original manufacturer of the manufactured structure under inspection process in place at the point of manufacture. To use the trailer as a truly mobile building the trailer's electrical panel must be wired as a feeder supplied panel board even if it was originally wired as Service Equipment. That means that the Equipment Grounding Conductors and the Grounded Current Carrying Conductors; that most of us call the neutral conductors; must be isolated from each other and the Grounded Current Carrying Conductors must not be bonded to the panel's enclosure nor to the feeder's Equipment Grounding Conductor. 

Electric cord is available in much larger gauges than the six gauge size that is commonly used for trailer pigtails but it is very uncommon to find receptacle outlets larger than fifty ampere pattern in a trailer service pedestal. If you need more power to the trailer than fifty amperes the larger cord is usually terminated in "Lug Pins" or pin adapters. Lug Pins are crimp on solid pins that are intended to be hooked up to electrical compression lugs rather frequently. They are used to avoid the conductor damage that would inevitably result from the frequent connection and disconnection of stranded wire. 

-- 
Tom Horne


----------



## Guest (Jan 31, 2014)

||Downhome|| said:


> never understood why a 3-way is called a 3-way when a 4-way should be a 3-way...
> would not mind some one explaining that...
> but they both have a "common"
> 
> so any one care to share?


A single pole light switch is actually a 2-way switch , on & off , therefore if you add another switch it becomes a 3-way etc. , etc .


----------



## FarmerDavid (Jul 16, 2012)

How many outlets should be on a circuit in the kitchen? With crockpots, coffee makers, and other various small appliances its not uncommon to get a large draw on a smaller number of outlets then is normally in use in other areas.


----------



## wharton (Oct 9, 2011)

FarmerDavid said:


> How many outlets should be on a circuit in the kitchen? With crockpots, coffee makers, and other various small appliances its not uncommon to get a large draw on a smaller number of outlets then is normally in use in other areas.


 Two dedicated, twenty amp circuits serving the countertop is the requirement. Outlets need to be ground fault protected. They cannot be located more than 4' apart and not more than 2' from the edge of the sink. I alternate my circuits, so that no two adjoining countertop receptacles are on the same circuit.


----------



## FarmerDavid (Jul 16, 2012)

I was told that I only need 1 GFCI and it will protect all the outlets in that circuit after the GFCI. Before I start to plan my layout can this be verified?


----------



## FarmerDavid (Jul 16, 2012)

wharton said:


> Two dedicated, twenty amp circuits serving the countertop is the requirement. Outlets need to be ground fault protected. They cannot be located more than 4' apart and not more than 2' from the edge of the sink. I alternate my circuits, so that no two adjoining countertop receptacles are on the same circuit.


Should that read not closer then 2' to the edge of the sink?


----------



## MushCreek (Jan 7, 2008)

No, it is no more than 2' from the edge of the sink. The rule is that no point on the counter top can be more than 2' from an outlet. So if you're dumb enough to put your toaster on the edge of the sink, you can still plug it in.

You can get by with one GFI, and it will protect the rest of the outlets wired after it, as long as it is installed correctly. I'm not sure how many outlets can be wired this way on any one circuit. Because a lot of kitchen appliances have a pretty big draw, I only put 4 outlets per circuit. Our new kitchen has 3 such circuits, plus dedicated separate outlets for the refrigerator and microwave.


----------



## wharton (Oct 9, 2011)

FarmerDavid said:


> I was told that I only need 1 GFCI and it will protect all the outlets in that circuit after the GFCI. Before I start to plan my layout can this be verified?


 Who is "telling you" and is it an installation that's being inspected? If so, the requirement for two twenty amp convenience outlet circuits servicing countertops has been an NEC requirement for as long as I've been licensed, and that's been 30 years now. This is, BTW a minimum requirement, and not the way I typically wire a kitchen. I also use separate circuits for the dishwasher, fridge, microwave, and lighting. If you are doing a job that needs to be approved, there are also strict rules for outlet placement on peninsulas, islands, and the adjoining dining area.


----------



## wharton (Oct 9, 2011)

FarmerDavid said:


> Should that read not closer then 2' to the edge of the sink?


Nope, I once saw a real "Richard Cranium" of an inspector flunk a job, and demand that two outlets in a tiled backsplash be relocated because they were 26" way from the sink.


----------



## FarmerDavid (Jul 16, 2012)

He didn't tell me that a kitchen only needed one circuit but that if a run had a GFCI as the first outlet of a run that all the outlets on that run were protected. 

I'm assuming that its a local guy that's done electric for 40 years that told me that. I've asked him questions on several projects over the years. I don't think he has any license and just does local work. We don't have any local code or inspectors. I understand that national code applies but there's no one to inspect it or anything to so with permits. 

Our current kitchen was all on two circuits when we bought the house. I put the lights, fridge, stove and microwave on their own. Put the dishwasher on one with a run of outlets. My wife likes to put a space heater on that run and it'll trip a breaker some when she does that and the dishwasher kicks on.


----------



## wharton (Oct 9, 2011)

David, that's why it's a good idea to run two circuits, keep the DW, micro, and fridge on separate circuits, and do your layout so that no two adjoining countertop outlets are on the same circuit. 

With regard to asking most local residential electrician for advice, it's an interesting quandary. Before code enforcement came to our area, I would typically at least double, or even triple the number of circuits run in my new homes compared to the local guys who did new construction. The difference is that they are working for low bid, and every penny counts, so they are very skilled at doing the least amount possible to make sure that the builder doesn't end up with unhappy customers, and they can still make a living. I have had one or two tell me that I am an idiot for doing all that work that "isn't necessary". The flip side of this is that my customers don't call to ask why they "can't vacuum in the spare bedroom while the TV is on in the master bedroom?" or why "they can't leave the crock pot on while they are at work, since they return to cold food and a tripped breaker", or "why there is only one outlet in the garage". Nothing wrong with how a typical residential electrician does their work, it generally safe, and meets minimum standards, but it leaves a LOT of room for improvement, and if you are doing your own work, it's a silly way to cut corners. Good luck.


----------



## MichaelZ (May 21, 2013)

Electricians cost a fortune, but you can reach a happy medium by finding a friend that is licensed to guide you through to do some of the work, paying him for his help. Much of the work is busy work that anyone can do regardless of experience - running lines, attaching outlets. You just need to use the right wire gauge and type and outlet type and have your friend get you started. Have your friend tell you what to do, then run the lines and outlets, and have your friend come back to see what you did. Once all the lines are to the box, your friend can inspect and finish things. If they are licensed realize that you will have to meet all code for them to do the job and put their name on it. This may mean expensive boxes with insulation flaps (that most people cut off so they can finish the drywall) and other things like expensive gfc circuit breakers. The gfc breaker is a good idea, but it is costly.


----------



## FarmerDavid (Jul 16, 2012)

You mentioned peninsulas. What special considerations need to be take there.


----------



## farmrbrown (Jun 25, 2012)

FarmerDavid said:


> You mentioned peninsulas. What special considerations need to be take there.


That they have to have at least one, and be located on the countertop. I think it's in section 250.52


----------



## wharton (Oct 9, 2011)

https://www.inkling.com/read/nfpa-n...handbook-2011/chapter-2/iii--required-outlets



This link is a solid, highly detailed explanation of outlet and circuit requirements in residential work. There may or may not need to be an outlet required for a peninsula, depending on many factors. In particular watch out for breakfast bar overhangs on the countertop, and do not install an outlet on the wall below IF the countertop overhangs the cabinet by more than 6". Other than that, you are allowed to install an outlet in the countertop, but it doesn't happen often, as it's expensive and involves a complex device that allows the outlet to pop up and down into the space below, or flip up like an old Corvette headlight. Both involve lots of planning, countertop cutting, and $150 on up for the unit. They definitely have a "cool" factor if you are building a bazillion dollar kitchen, but most of us aren't heading down that road.:grin:


----------



## FarmerDavid (Jul 16, 2012)

How safe are these?



I have to assume safer then this:

Seeing alot if both in this house.


----------



## wharton (Oct 9, 2011)

The bakelite device is interesting. Is it a splice point, something you would T-tap out of? Or, is there a push button in the center of the cover? What was the point of skinning the Romex back and attaching it to that thing? As for whether it's OK? No, not anymore. Might be legal if installed in the 1940s, still in service, properly mounted to a solid surface, and undisturbed for all these years, but it looks like none of the above apply.

As for the old, cloth covered Romex. It can be relatively safe, IF it is undisturbed from original, and not overloaded. The splice itself is no longer legal, since it's not in a legitimate junction box and it was not done with wire nuts. You will probably find if you pull the old friction tape off of those wires that they were twisted and then soldiered. Old cloth Romex typically has no ground, and the rubber insulation (under the cloth wrap) is usually too brittle to safely manipulate. Looks to me like anything like you pictured would be best if it was removed and coiled up in an old garbage can, waiting to sell it at the scrap yard.


----------



## FarmerDavid (Jul 16, 2012)

It was a splice. I'd removed the second wire before the pic. I'm not sure when they were installed but they are def not fastened I anything. 

Originally the house was built in the 20's without indoor plumbing or electrical. I'm not sure when they were added but both are kind of a hodgepodge of different renovations to the house. Both are being completely replaced.


----------

