residential outlets

[roger3829]

"4 bedrooms, 5 receptacles in each bedroom, (no lights) plus smokes on 1 AFCI"
Yes, allowed
Bad idea but allowed

"The rest of the house on regular breakers"
Kinda. . It would really be "the rest of the house" after you put in a 2nd AFCI
You'll need that 2nd AFCI for the bedroom lights because you don't have it on the same circuit as the plugs
"5 receptacles in each bedroom, (no lights)"

Who said anything about installing any lights? They are not required.

 

[dnem]

Who said anything about installing any lights? They are not required.

Oh, Yeah !

I hate it when you're right !

 

[tryinghard]

In non-dwelling, 220-44 allows the receptacles to be calculated with the lighting.

 

[dnem]

In non-dwelling, 220-44 allows the receptacles to be calculated with the lighting.

That's not what 220.44 is talking about.
You have to add light and plug load separately for commercial. . Only lighting goes by square footage. . 220.44 is the next step which allows you to combine them in order to reduce the load needed to be calculated for the service or the feeder. . It's demand factor.

 

[tryinghard]

That's not what 220.44 is talking about.
You have to add light and plug load separately for commercial. . Only lighting goes by square footage. . 220.44 is the next step which allows you to combine them in order to reduce the load needed to be calculated for the service or the feeder. . It's demand factor.

What do you mean? It is talking about calculating the receptacle load with the lighting to size a feeder, often the lighting is separate from receptacles because the lighting is continuous and calculated at 125% and receptacles are non-continuous, see Annex D3.

220-12 is the minimum for calculating lighting loads; most often the actual lighting is used in the panel schedules because it is more than the requirement of 220-12.

 

[LawnGuyLandSparky]

"4 bedrooms, 5 receptacles in each bedroom, (no lights) plus smokes on 1 AFCI"
Yes, allowed
Bad idea but allowed

"The rest of the house on regular breakers"
Kinda. . It would really be "the rest of the house" after you put in a 2nd AFCI
You'll need that 2nd AFCI for the bedroom lights because you don't have it on the same circuit as the plugs
"5 receptacles in each bedroom, (no lights)"

IF there are bedroom lights. I was thinking spec / tract housing, outlet closest to bedroom door switched, bare code minimum.

 

[dnem]

What do you mean? It is talking about calculating the receptacle load with the lighting to size a feeder, often the lighting is separate from receptacles because the lighting is continuous and calculated at 125% and receptacles are non-continuous, see Annex D3.

220-12 is the minimum for calculating lighting loads; most often the actual lighting is used in the panel schedules because it is more than the requirement of 220-12.

That's right for 220 Part Three
But my point was that you have to set up the numbers in Part Two first.

Residential gets the plug load reduction upfront in 220.14(J). . And the reduction is 100%.
Commercial has to add a plug load in and then go to parts 3+4 to get the demand reduction in 220.44 + 220.82(B).

During the part 2 portion of the calculation, for commercial you have to add plug load according to actual load or, if none, according to 180va per plug. . Then you go to part 3 and get your demand reduction.

But for residential, you get the reduction built right into part 2 because you don't have to add anything for plug load.

 

[tryinghard]

David,

Somehow were on a different topic then the original posts

The OP is asking about residential outlets as per their thread name:

is there a code section that specifies light circuts and receptacle circuts must be seperate?

No there is not

so would that mean you could put all bedroom outlets on one arc-fault, lights smoke and receptacles?

Yes you can.

Then you quoted

...Residential gets the plug load reduction upfront in 220.14(J). . And the reduction is 100%....But for residential, you get the reduction built right into part 2 because you don't have to add anything for plug load.

I think the topic moved to Article 220 as example because the calculations account for these together therefore it's okay to install them together.

At minimum one must calculate the general lighting load at 3VA per livable space this includes the receptacles. The calculation for a residence adds all the "General Load" together then adjusts KVA by including the first 10KVA at 100% and the remaining at 40% (Annex D2(c) is a common example used).

What do you mean by "plug load reduction upfront"?

 

[dnem]

The OP is asking about residential outlets as per their thread name:

Yeah, but in post #18, I said that I was going to assume that his reference to residential was a mistake because his profile says he's a senior electrical inspector.

so would that mean you could put all bedroom outlets on one arc-fault, lights smoke and receptacles?

Yes you can.

Yes you can, except for 210.11(CC)

What do you mean by "plug load reduction upfront"?

By "upfront" I mean that there's no residential receptacle load put in in part 2 so there's no reduction in parts 3 or 4. . For commercial, there's a load added in part 2 [up front] and then a demand factor reduction in parts 3 + 4 [on the back end].

Commercial adds in a 180va [or specific load] in part 2 [220.14(L)]. . Then gives you a demand reduction in part 3 [220.44].

Residential doesn't add a receptacle load in part 2, "No additional load calculations shall be required for such outlets." [220.14(J)]. . And so you don't get the demand reduction in part3 [220.44].

I'm told by people that have done a ton for load calcs that the Optional Method of part 4 almost always gives you the lowest number for large houses. . I'm sure part of the reason is that 220 lets you "doubledip" for residential part 4 Optional Method. . You get zero for your receptacle load in 220.14(J) and only have to add in the 3va per square foot lighting. . And then you get the "doubledip" in 220.82(B) for the portion of your general load that goes over 10kva.

 

[tryinghard]

...By "upfront" I mean that there's no residential receptacle load put in in part 2 so there's no reduction in parts 3 or 4....Residential doesn't add a receptacle load in part 2, "No additional load calculations shall be required for such outlets." [220.14(J)]. . And so you don't get the demand reduction in part3 [220.44].

I just want to clarify residential receptacles are accounted for in the general lighting load specifically "All general-use receptacle outlets are included in the general lighting load calculations of 220-12", this is where they get added in is the 3VA per square foot.

Commercially the lighting is calculated as a continuous load and the receptacles are not, see Annex D3 for a good example.