How many receptacles on a circuit

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electrifier

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I get asked frequently how many receptacles are allowed on a 15 amd and a 20 amp residential circuit. I hear the wrong answer most of the time. How do you calculate the number of receptacles allowed on a convenience outlet circuit in a finished part of the house?
 
electrifier said:
I get asked frequently how many receptacles are allowed on a 15 amd and a 20 amp residential circuit. I hear the wrong answer most of the time. How do you calculate the number of receptacles allowed on a convenience outlet circuit in a finished part of the house?
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The answer is, as many as you want to put on them. There is no limit in residential installations as far as the NEC is concerned. If you have local codes or rules, that would be another story.

Roger
 
roger said:
The answer is, as many as you want to put on them. There is no limit in residential installations as far as the NEC is concerned. If you have local codes or rules, that would be another story.

Roger
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Seriously ? No limit ? Yeah , I got some bad advice too . :mad:
 
At one time was there something in the NEC where it was 180 watts per outlet?? That rings a bell in my brain, but it might be a loose wire ;)
 
djohns6 said:
Seriously ? No limit ? Yeah , I got some bad advice too . :mad:
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Seriously, receptacles on general lighting circuits require no additional calculating after the required number of circuits are provided, 220.14(J)

(J) Dwelling Occupancies.
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In one-family, two-family, and multifamily dwellings and in guest rooms or guest suites of hotels and motels, the outlets specified in (J)(1), (J)(2), and (J)(3) are included in the general lighting load calculations of 220.12. No additional load calculations shall be required for such outlets.

(1) All general-use receptacle outlets of 20-ampere rating or less, including receptacles connected to the circuits in 210.11(C)(3)

(2) The receptacle outlets specified in 210.52(E) and (G)

(3) The lighting outlets specified in 210.70(A) and (B)
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Roger
 
We have had _extensive_ threads on just this very topic.

For what its worth, and this is just my opionion: while there is no limit to the number of receptacles on a circuit, you do have limits on the _area_ supplied by a single branch circuit. You have to allocate a certain number of VA per square foot, you have to allocate sufficient general purpose circuits to supply this load, and you have to divide the load amongst these circuits. Net result is that each circuit can supply so many square feet.

-Jon
 
BLACK4TRUCK said:
At one time was there something in the NEC where it was 180 watts per outlet?? That rings a bell in my brain, but it might be a loose wire ;)
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220.14(H),(I), and (L), for other than dwelling units.

Roger
 
As Winnie said, this has already been the matter of extensive debate. I have always held to the belief that there is no limit anywhere. I believe that since the 180 VA per square foot is in the calculation article, and not in the branch circuit article, you don't have to use it during your design process.
 
I recall someone doing some real-world tests on this subject. Calculated how much power was lost for each splice. Then calculated the voltage drop for a known number of splices. I don't know if this person assumed no load, or a fully-loaded 15- or 20-amp circuit, but the number, at least mathematically, was outrageous.

Something like 35,000 receps.
 
charlie b said:
I have always held to the belief that there is no limit anywhere. I believe that since the 180 VA per square foot is in the calculation article, and not in the branch circuit article, you don't have to use it during your design process.
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I am among those who agree with Charlie on this. Besides, for most non-residential wiring, few receptacle circuits are truely general purpose; most are load-specific.
 
LarryFine said:
I am among those who agree with Charlie on this. Besides, for most non-residential wiring, few receptacle circuits are truely general purpose; most are load-specific.
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I agree, yet the misconceptions are often cited as fact/ code, not only by people outside the profession. My immediate supervisor cited the 180va per receptacle in a resi dwelling not less than a year ago and when I said he was wrong, he said it was code at some point. He is a carded Master Electrician. So much for CEUs.:mad:
 
djohns6 said:
Seriously ? No limit ? Yeah , I got some bad advice too . :mad:
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Let me guess:
No more than 8 on a general purpose circuit.
No more than 4 on kitchen circuits.
If so, those are 2 of 3 Baton Rouge (and a few surrounding areas) amendments.
The 3rd is no romex in commercial.
If you heard that in another area then maybe it was bad advice:D
 
jumper said:
I agree, yet the misconceptions are often cited as fact/ code, not only by people outside the profession. My immediate supervisor cited the 180va per receptacle in a resi dwelling not less than a year ago and when I said he was wrong, he said it was code at some point. He is a carded Master Electrician. So much for CEUs.:mad:
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Jumper,
From my perspective, Don't jump too quick on your master.
Running a business can eat up all your time,
with little left over to keep track of ALL the codes.
I have to bite my tongue all the time,
when my master points out 'A Trade Practice' to be 'The Code'.

Many specific applications are covered by 'trade practice' concepts
which may be safer or better service to a client,
or may include some local code from the many little places around here.

Several times there has been a specific AHJ who 'Expected',
and the master made certain that we 'Complied' before the inspection.

IMO, and from a practical point of view,
180va is a good way to keep from OverLoading any circuit.

I have gone through resi jobs using this,
and find that it allows for Small Space Heaters and Big TVs, etc,
on any single circuit. Never can tell what modern folks will plug in.

The client never likes to run out of electric power.
(Of course, I was arranged to charge for the extra time and matl.)

Jumper, your Comments are welcome.
 
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winnie said:
For what its worth, and this is just my opionion:
while there is no limit to the number of receptacles on a circuit,
you do have limits on the _area_ supplied by a single branch circuit.
You have to allocate a certain number of VA per square foot,
you have to allocate sufficient general purpose circuits to supply this load,
you have to divide the load amongst these circuits.
Net result is that each circuit can supply so many square feet.
-Jon
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Winnie,

Good thinking, the 'Combo-Approach'.

I need to re-read the code sections and check this out.
But either way, that is a good 'Trade Practice' at least.

I like that combo-approach. Covers all bases.
 
glenne77is
I agree with your comments. My problem is that my immediate supervisor is not a harried EC. The situation was when a HVAC tech asked me the receptacle question, and my supervisor said 180va without thinking and walked off. I actually explained to the tech pretty much what you described, that usually code is not enough to be efficient in this situation. Later that day I told supervisor real answer, and his reply was "it was code at some point". I am often wrong, that is why i joined this forum:D, and when it is pointed out, I say "thank you", instead of making excuses.
 
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