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Discussion Starter · #1 · (Edited)
Hello,

I have calculated the general lighting load for one-family dwelling, this in according to the Table 220.12, and as per my results, i can install 2 branch circuits of 20 A in the first floor of the house and 2 more in the second floor.

In the first floor i was thinking to use one circuit for lighting and the other one for the receptacles, however (here is my doubt), i have 35 receptacles outlets, so i wonder, it would not be too many outles for a 20A circuit?

Thanks in Advance,

Regards, Saludos.

note: sorry for the post title, receptacule means receptacle.
 

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Sal,
T220.12 references 220.14(J), which essentially lifts the requirements of 220.4 asking for a max of 13 outlets on a 20A circuit in dwellings

Basically, for other than dedicated loads & circuitry, you could put the entire dwelling on one general use circuit.

~CS~
 

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Basically, for other than dedicated loads & circuitry, you could put the entire dwelling on one general use circuit.
I think it is important to qualify that statement with an area size restriction.

One 20A general lighting and receptacle circuit would be sufficient in a 800 sq ft apartment, but not in a 4000 sq ft house.

There is, however, no limit to the amount of receptacles allowed per general lighting and receptacle circuit in a dwelling.
 

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I agree Barjak :thumbsup:

My impression is that the NEC didn't wish for receptacle 14 or 15 on a 20A circuit to break the older 20-24 cir panel constraints, and/or maybe rid the resi scene of the evil extension cord.....

~CS~
 

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Discussion Starter · #5 ·
Recommendation

I think it is important to qualify that statement with an area size restriction.

One 20A general lighting and receptacle circuit would be sufficient in a 800 sq ft apartment, but not in a 4000 sq ft house.

There is, however, no limit to the amount of receptacles allowed per general lighting and receptacle circuit in a dwelling.
Hello,

Thanks for your responses,

My concern is due to the idea that the use of electrical appliances in the home has increased and therefor also the load, but I think that all this is reviewed at each new version of NEC.

Here in Costa Rica many electricians use a parameter of 12 to 14 receptacles per each 20A breaker, and in the Panel board schedule they assign a load of 1500 VA per circuit, however there is not a criterion based on the NEC for this practice.

In this case, which one is your recommendation? Should i place the 35 receptacles in one 20A circuit? This quantity of receptacles is due that i am respecting the minimum distances given by the NEC.

Thanks in advance for your responses.
 

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Hello,

Thanks for your responses,

My concern is due to the idea that the use of electrical appliances in the home has increased and therefor also the load, but I think that all this is reviewed at each new version of NEC.

Here in Costa Rica many electricians use a parameter of 12 to 14 receptacles per each 20A breaker, and in the Panel board schedule they assign a load of 1500 VA per circuit, however there is not a criterion based on the NEC for this practice.

In this case, which one is your recommendation? Should i place the 35 receptacles in one 20A circuit? This quantity of receptacles is due that i am respecting the minimum distances given by the NEC.

Thanks in advance for your responses.
First, are you sure none of these 35 are in the laundry, bath, kitchen, dining, or other similar room requiring dedicated circuits?

Second, not all of the receptacles in a dwelling always have something plugged in and running, they are there because they are required so that something can be plugged in if needed.

BTW, What is the square footage?
 

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Discussion Starter · #7 ·
Mistake.

First, are you sure none of these 35 are in the laundry, bath, kitchen, dining, or other similar room requiring dedicated circuits?

Second, not all of the receptacles in a dwelling always have something plugged in and running, they are there because they are required so that something can be plugged in if needed.

BTW, What is the square footage?
Hi,

Wow thanks for your prompt answer,

You have given me a light about something that I was doing wrong.

I have included in the load for general receptacles the receptacles located in the dining room ,breakfast room and pantry instead of including them in the kitchen dedicated circuits.

The dwelling area is about 220.7 sq m that is about 2375 sq ft (including both floors). The area for the first floor is 1281 sq ft.

My new receptacles number after to correct the mistake is 29, what do you think, is it ok for a 20A circuit?

For you, what should be the maximum number of receptacles for a 20A circuit?(of course under understanding that is a personal opinion)

I have a doubt regarding this issue, this load that is based on the area of the dwelling is calculated as a minimum according to the NEC, but what about if i decide to add a circuit of 20A in order to include more receptacles, this would represent a new load of 2400VA, should I add this new load to the general lighting in order to apply the demand factors?, or where should be located this new load in my calculus?

Again, Thanks for your help!
 

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as you said, the NEC doesn't specify, so you could very well do that. However, this may not be in the best interest of the inhabitants of the particular dwelling. As noted in the NEC (article 90 or preface), it is not a design manual, but a minimum guide to provide for the bare minimum requirements to the safe use of electricity. Not, perhaps, the best use of the electricity, nor the most convenient use - those are design issues. Personally, I would never put that many receptacles on on ckt in a house.
 

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It is a concept I had trouble grasping at first, too.

For me, it helped to think more about dividing up the circuits evenly across the square footage, than how many receptacles were on each circuit. When you do this, it sometimes becomes clear the need to add a circuit simply for convenience when wiring, or to divide the load. You do not need to add the VA for any new general L+R circuit to the service calc as it is based on square footage.

In your situation, 2375 sq ft equals (3) 20A circuits.

If you want to divide upstairs and down (which I would consider doing),
1281 sq ft downstairs equals (1.6) circuits, leaving (1.4) circuits upstairs.

Since you can't install (0.6) breakers, you might consider having 4 or even 5 total circuits (2 or 3 downstairs and 2 upstairs).
 

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Most of would probably wire a dwelling that size back to breakers marked >>
1)1st flr front
3)1st flr rear
2)2nd flr front
4)2nd flr rear
5)basement gfci & all outside receptacles


~CS~
 

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Hello,

I have calculated the general lighting load for one-family dwelling, this in according to the Table 220.12, and as per my results, i can install 2 branch circuits of 20 A in the first floor of the house and 2 more in the second floor.

In the first floor i was thinking to use one circuit for lighting and the other one for the receptacles, however (here is my doubt), i have 35 receptacles outlets, so i wonder, it would not be too many outles for a 20A circuit?

Thanks in Advance,

Regards, Saludos.

note: sorry for the post title, receptacule means receptacle.
Me thinks your better off doing a load calculation and thinking about what things are likely to be plugged in to the various outlets !
Then you can add up the numbers and find how much power you will need !
So if they all had only small loads on them,
then putting them all on one circuit might not be a problem !
But on the other hand if large loads are likely,
like hair dryers, kettles, heaters, a/c units.
Then it clearly wont work.
 

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cal62
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cal1947

Me thinks your better off doing a load calculation and thinking about what things are likely to be plugged in to the various outlets !
Then you can add up the numbers and find how much power you will need !
So if they all had only small loads on them,
then putting them all on one circuit might not be a problem !
But on the other hand if large loads are likely,
like hair dryers, kettles, heaters, a/c units.
Then it clearly wont work.
you also need a 20 amp circuit for bathrooms gfi prtected
 
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