How to distribute the load in a dwelling.

Status
Not open for further replies.

iwire

Moderator
Staff member
Location
Massachusetts
It does indirectly, other sections then tell you to evenly proportion those circuits one derived from 3va per foot.

I disagree with your conclusions.

How many sq ft does a receptacle cover?

How many sq ft does a lighting outlet cover?

When we have a room with more than one circuit how do figure out how many sq ft each circuit is handling?

Reason number 53 why I don't think your are an electrian as a profession. :)
 

mbrooke

Batteries Included
Location
United States
Occupation
Technician
I disagree with your conclusions.


How many sq ft does a lighting outlet cover?

When we have a room with more than one circuit how do figure out how many sq ft each circuit is handling?

Reason number 53 why I don't think your are an electrian as a profession. :)


My bigger question is why do you need to character assassinate me over and over?

Going back to what I said:

3va per foot is used to derive the minimum amount of general use circuits for a dwelling. Once that number is known, code requires they be evenly distributed.

A circuit can have an unlimited number of receptacles and in theory an unlimited number of lights. A room can have an unlimited number of circuits or only one circuit. That not what I am arguing.

Point is, those general use circuits must be evenly distributed. Yes "even" is a very relative term, and nothing is written in stone on that, but the intent imo is that a 2000 square foot home does not end up with a single circuit covering 2 beds, 2 bath vanity lights, 1 living room, basement lights, powder room, den, and then the remaining 3 circuits only feed single hall receptacles: 1 upstairs two down stairs.
 

iwire

Moderator
Staff member
Location
Massachusetts
My bigger question is why do you need to character assassinate me over and over?

Why must you claim to be what you are not?:huh:

I am not tying to assassinate your character, being something other than an electrician is not a bad thing and certainly not an insult. But I abhor untruths and claiming to be an electrician when you are not one is kind of odd. Have you held an electrical license in any US state?


Anyway, moving on. :)


3va per foot is used to derive the minimum amount of general use circuits for a dwelling.

I think we all agree with that.

Once that number is known, code requires they be evenly distributed.

How is that done?

Seriously, explain how you do that when you wire houses because I have been doing this a long time and I have no idea how to distribute something evenly that does not have a value.


A circuit can have an unlimited number of receptacles and in theory an unlimited number of lights. A room can have an unlimited number of circuits or only one circuit. That not what I am arguing.

Again we agree.

Point is, those general use circuits must be evenly distributed. Yes "even" is a very relative term, and nothing is written in stone on that, but the intent imo is that a 2000 square foot home does not end up with a single circuit covering 2 beds, 2 bath vanity lights, 1 living room, basement lights, powder room, den, and then the remaining 3 circuits only feed single hall receptacles: 1 upstairs two down stairs

So tell me how that is done, don't you dare say 'evenly' :lol: tell me what perimeters the code is requiring we use to distribute this evenly?
 

iwire

Moderator
Staff member
Location
Massachusetts
In the concept of this code, what "loads" are to be evenly distributed then? Or how do you evenly distribute them? Or do you just get to ignore this code section because it is poorly written?

How about you?

Can you tell me how to evenly distribute something that has no assigned value?
 

Strathead

Senior Member
Location
Ocala, Florida, USA
Occupation
Electrician/Estimator/Project Manager/Superintendent
I disagree with your conclusions.

But you aren't making any conclusions yourself. What effort do, or would you go to to comply with 210.11(B) As I read through the thread and think about it closely I can see that the likely argument is to proportion the square footage up evenly by circuit. As 220 assigns 3va per square foot so that is the only way you can really look at a "load" in that perspective I guess, since as you stated, a receptacle isn't a load.
 

iwire

Moderator
Staff member
Location
Massachusetts
But you aren't making any conclusions yourself. What effort do, or would you go to to comply with 210.11(B)

I think it is virtually impossible to comply with and would be very surprised if any inspector has failed a job based on that unless the installer only installed breakers on one line and left the other open.

As I read through the thread and think about it closely I can see that the likely argument is to proportion the square footage up evenly by circuit.

OK, lets do that.

How many sq ft does one outlet cover?
 

Strathead

Senior Member
Location
Ocala, Florida, USA
Occupation
Electrician/Estimator/Project Manager/Superintendent
I think it is virtually impossible to comply with and would be very surprised if any inspector has failed a job based on that unless the installer only installed breakers on one line and left the other open.



OK, lets do that.

How many sq ft does one outlet cover?

I agree with the first part, and as I have stated repeatedly I really don't like 220.12 and 210.11. For the second part, it isn't a question that has any validity. It is "how many square feet does a circuit cover that matters in this division. Because as we both know your question is misleading and a trick.
 

mbrooke

Batteries Included
Location
United States
Occupation
Technician
Why must you claim to be what you are not?:huh:

I am not tying to assassinate your character, being something other than an electrician is not a bad thing and certainly not an insult. But I abhor untruths and claiming to be an electrician when you are not one is kind of odd. Have you held an electrical license in any US state?

Because I have an extensive history of doing hands on electrical work both rough-ins and trouble shooting. I am not oblivious to the real world. I may not do it right now at the moment, but that does not mean I did it in the past. Insisting the same thing over and over without any proof serves no purpose other then to de-rail the discussion at hand. What set this off was when I claimed inspectors ought to question the NEC regarding AFCIs and you took that at face value. I never said that inspector pick and choose what codes they follow, rather that inspectors should question the code, especially when fraud is being passed into law. Im sorry if that upset you, but thats my opinion regarding inspectors and I stand by it 100%.



How is that done?

By the discretion of the installer.

Seriously, explain how you do that when you wire houses because I have been doing this a long time and I have no idea how to distribute something evenly that does not have a value.


Ok, here is how I did it. 1,800 square foot code minimum home, 4 15 amp circuits. 1 15 amp circuit goes up and wraps around the living room walls, circuit branches off at receptacle boxes to switch boxes above along the runs which feed back porch lights, back hall lights, down stairs half bath lights, and back hall receptacles. A 14-2 may drop directly below to a basement light (pull string, nice try:p). Second 15 amp circuit runs feeding the front of the home, feeding outlets along along the front half of the home, 14-2 up the the front door switch box for outside lights and hall light via 14/3, 14-2 from the hall light to the dinning room lights (switch leg for control), hits up other lights like the kitchen and over the sink lights and hood in some cases. Third and forth are via 14/3 MWBC that runs upstairs. The circuit split off in the hall. Circuit one feeds all of the master bedroom and master bath lights. Circuit two takes on the halls lights, second bedroom and upstairs hall bath. Exterior and bath rectacles via a separate GFCI branch circuit (latter changed to baths only to follow the NEC).


Thus, in my eye this is an even distribution of those minimum circuits.


If I did it where 1 circuit did 2 beds, 3 baths, living room, den, ect ect with the remaining three only doing random outlets Id call that a code violation.




So tell me how that is done, don't you dare say 'evenly' :lol: tell me what perimeters the code is requiring we use to distribute this evenly?

As I said, its more relative. Its not set in stone, but Id think common sense would tell us which in the above example meets the intention of the code.
 

kwired

Electron manager
Location
NE Nebraska
The code says the circuits will be distributed evenly. When they are installed they are even. If a person plugs loads in that exceed the circuit, that is a usage problem, not an installation problem. I don't like it. I think the code should place some sort of value on receptacles for purposes of sizing branch circuits at least, but in a residence it doesn't.
And the load density can vary so greatly that there is no one value that fits all solution - NEC is not supposed to be a design manual, surprisingly they so far have left this section alone where they have turned several other areas into design requirements.

They do recognize that some areas typically do have higher loads, and I would assume is why they require at least two SABC's (on 20 amp circuits), a 20 amp laundry circuit, a 20 amp circuit to the bathroom receptacle(s) and more recently wanting limitations on the circuits to the garage. All of those having restrictions on what else may be on those circuits. None of those present requirements are completely perfect either though and the designer still needs to make some decisions on what will be best for the user. 2 SABC's may not be sufficient for some homes but others could possibly do fine with just one.
 

mbrooke

Batteries Included
Location
United States
Occupation
Technician
And the load density can vary so greatly that there is no one value that fits all solution - NEC is not supposed to be a design manual, surprisingly they so far have left this section alone where they have turned several other areas into design requirements.

They do recognize that some areas typically do have higher loads, and I would assume is why they require at least two SABC's (on 20 amp circuits), a 20 amp laundry circuit, a 20 amp circuit to the bathroom receptacle(s) and more recently wanting limitations on the circuits to the garage. All of those having restrictions on what else may be on those circuits. None of those present requirements are completely perfect either though and the designer still needs to make some decisions on what will be best for the user. 2 SABC's may not be sufficient for some homes but others could possibly do fine with just one.

I think the 20amp for the washer and dinning room is overkill imo, at least here.
 

kwired

Electron manager
Location
NE Nebraska
I think the 20amp for the washer and dinning room is overkill imo, at least here.

There is no 20 amp requirement for the washer though, it is for the "laundry". It can supply more then just the washer in the "laundry area".

Dining room - many cases is seldom loaded, but don't forget it can be on with other items allowed on the SABC's.

Other cases where you have someone that hosts frequent parties more then one circuit may be needed for their "style" of hosting these parties. If they have those 1500 watt heated warmers/cookers and place them in the dining room they will need a circuit for every one used, or even if they throw in some heated beverage appliances they can be a problem as well.
 

mbrooke

Batteries Included
Location
United States
Occupation
Technician
There is no 20 amp requirement for the washer though, it is for the "laundry". It can supply more then just the washer in the "laundry area".

Dining room - many cases is seldom loaded, but don't forget it can be on with other items allowed on the SABC's.

Other cases where you have someone that hosts frequent parties more then one circuit may be needed for their "style" of hosting these parties. If they have those 1500 watt heated warmers/cookers and place them in the dining room they will need a circuit for every one used, or even if they throw in some heated beverage appliances they can be a problem as well.



True, but in the case of the laundry area when the washer is just in a closet a 15 amp circuit should be allowed.
 

kwired

Electron manager
Location
NE Nebraska
True, but in the case of the laundry area when the washer is just in a closet a 15 amp circuit should be allowed.

I'd say if there is a built in ironing center - even if not in the same closet as the washer - it would be permitted on the same circuit, or if there were also a 120 volt gas dryer it can be on the same circuit.
 

FREEBALL

Senior Member
Location
york pa usa
I know years back we calculated the load but even still kept it to about 4-6 recpts. to a circuit just for the reason you don't know what will be plugged in. But now with AFCI rules it is difficult to be competitive by doing that. You stick to the basics and if home owner wants added outlets its extra. Albeit it was still somewhat costly to do this in the past, and I never liked multiwire circuits with the hazard of losing a neutral, but now when a breaker will cost you 40.00 a pc. you have to stick to what passes code.
 

mbrooke

Batteries Included
Location
United States
Occupation
Technician
I know years back we calculated the load but even still kept it to about 4-6 recpts. to a circuit just for the reason you don't know what will be plugged in. But now with AFCI rules it is difficult to be competitive by doing that. You stick to the basics and if home owner wants added outlets its extra. Albeit it was still somewhat costly to do this in the past, and I never liked multiwire circuits with the hazard of losing a neutral, but now when a breaker will cost you 40.00 a pc. you have to stick to what passes code.

And this is where AFCIs backfired. Fewer circuits under more stress :happyno: I think we all miss those days with 14/3. :(
 

mbrooke

Batteries Included
Location
United States
Occupation
Technician
I'd say if there is a built in ironing center - even if not in the same closet as the washer - it would be permitted on the same circuit, or if there were also a 120 volt gas dryer it can be on the same circuit.

True, but imo the NEC should leave that up to the sparky. Condos with a washer and dryer tucked into a closet would be a good exception to the 20 amp rule.
 

don_resqcapt19

Moderator
Staff member
Location
Illinois
Occupation
retired electrician
In the concept of this code, what "loads" are to be evenly distributed then? Or how do you evenly distribute them? Or do you just get to ignore this code section because it is poorly written?
Exactly...it is a rule that cannot be applied. There is no way to know what the loads will be and where they will be.
 

kwired

Electron manager
Location
NE Nebraska
True, but imo the NEC should leave that up to the sparky. Condos with a washer and dryer tucked into a closet would be a good exception to the 20 amp rule.

It is still up to the sparky whether he wants to run one circuit to washer, one to dryer (120 volt gas dryer), one to ironing center - or he can put all three on one "laundry circuit".

Next question may be if you had run separate circuits to each if they are all "laundry circuits" and need to be 20 amps and figured as a 1500 VA load, yet one 20A circuit at 1500 VA is acceptable:huh:
 

iwire

Moderator
Staff member
Location
Massachusetts
True, but imo the NEC should leave that up to the sparky. Condos with a washer and dryer tucked into a closet would be a good exception to the 20 amp rule.

Why is it that in one thread you are saying the ampacity tables are not restrictive enough yet in other threads you say the NEC is too restrictive?

I get the feeling your idea of a code book is one on an eraser board that you can change to suit your needs at will. :D
 
Status
Not open for further replies.
Top