Number of recepts on a 20A branch circuit

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LarryFine said:
Notice that the rule in question specifies "receptacle outlets" and not "receptacles."
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Exactly. I specifically asked about "outlets" and get told about "receptacles." I thought the question was clear by the context of the thread as well.

We've recently had a thread where everyone says a duplex receptacle counts as two outlets. For example, that a single 15A duplex is okay on a 20A dedicated branch ckt. And this thread shows where the NEC is saying a single duplex is one outlet, which would mean that's not okay.
 
MAC702 said:
Exactly. I specifically asked about "outlets" and get told about "receptacles." I thought the question was clear by the context of the thread as well.

We've recently had a thread where everyone says a duplex receptacle counts as two outlets. For example, that a single 15A duplex is okay on a 20A dedicated branch ckt. And this thread shows where the NEC is saying a single duplex is one outlet, which would mean that's not okay.
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Did you read 220.14(I)? This is about load calculations only. Its about the load for each yoke not each receptacle.

(I) Receptacle Outlets. Except as covered in 220.14(J) and
(K), receptacle outlets shall be calculated at not less than
180 volt-amperes for each single or for each multiple receptacle
on one yoke. A single piece of equipment consisting of a
multiple receptacle comprised of four or more receptacles
shall be calculated at not less than 90 volt-amperes per receptacle.
This provision shall not be applicable to the receptacle
outlets specified in 210.11(C)(1) and (C)(2).
 
So is the Exhibit from the OP incorrect as it shows more than 10 or 13 ( respectfully)
 
Sierrasparky said:
So is the Exhibit from the OP incorrect as it shows more than 10 or 13 ( respectfully)
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The Exhibit I see in the OP shows 10 devices (yokes) on a 15 and 13 on the 20.
220.14(I) doesn't state 180va per individual receptacle. It states 180va per yoke. This doesn't meant that each yoke can only be considered 1 receptacle.
 
MAC702 said:
We've recently had a thread where everyone says a duplex receptacle counts as two outlets. For example, that a single 15A duplex is okay on a 20A dedicated branch ckt.
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How's that? 210.21(B)(1) refers to a "single receptacle" while 210.21(B)(2) refers to a branch circuit supplying "two or more receptacles or outlets". So there is no ambiguity there for the case of only one 15A duplex receptacle on a 20A dedicated branch circuit: it is two receptacles at one outlet, 210.21(B)(1) does not apply, and 210.21(B)(2) does apply.

Cheers, Wayne
 
MAC702 said:
We've recently had a thread where everyone says a duplex receptacle counts as two outlets. For example, that a single 15A duplex is okay on a 20A dedicated branch ckt. And this thread shows where the NEC is saying a single duplex is one outlet, which would mean that's not okay.
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No, a duplex receptacle is two receptacles, but one outlet. A 15a duplex receptacle is allowed on a 20a circuit, but a single 15a receptacle is not.
 
The illustration labeled 220-4 is for commercial and industrial locations only.

For residential the number of outlets on a 15 or 20 amp circuit is unlimited. On general use circuit, some of these outlets will be lighting outlets. That is why the illustration is commercial...there are no lightning outlets pictured. So you possibly could have 30+ outlets on a 15 amp circuit in residential.
The requirement is 3 watts per square foot. So for a 2400 sf house, four 15 amp circuits or three 20 amp circuits minimum.
Of course the small appliance circuits and now the garage receptacle circuits and a few others feed receptacles only, but the number of outlets is not limited.
 
augie47 said:
210.21(B)(2) is for "two or more receptacles".
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Of course. Got it thanks.

A couple more thoughts:

210.11 says that you must supply branch circuits for lighting and appliances to supply the loads calculated in accordance with 220.10.
210.11(A) goes on to say that the minimum number of branch circuits shall be determined from the load calculations. I take that to mean the load calculations in Article 220. Doesn't this force you to use 180VA at a minimum for each yoke when determining the quantity of branch circuits you need? And thereby having a maximum # of recepts on a branch for commercial applications?

And on a related note, while I understand it's code and not a design guideline, can anyone provide an explanation as to why the code would not allow a single 15A recept on a 20A branch circuit, but would allow a duplex 15A receptacle on a 20A branch circuit? The same goes for allowing a simplex 20A recept on a 15A OCP, but not allowing multiple 20A receptacles on a 15A OCP.
 
AS far as the 180va question, note 220.14(I) where the 180va is mentioned states "except as covered in 220.14(J) for dwelling units where the 180va is not included.
 
shespuzzling said:
...can anyone provide an explanation as to why the code would not allow a single 15A recept on a 20A branch circuit, but would allow a duplex 15A receptacle on a 20A branch circuit? The same goes for allowing a simplex 20A recept on a 15A OCP, but not allowing multiple 20A receptacles on a 15A OCP.
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A duplex receptacle is no different than two simplex receptacles, so in either case you have more than one receptacle on the ckt.

We also allow a 50A device on a 30 or 40A ckt, very commonly seen with ranges and welding machines, so they can use the most common device for that type of equipment, regardless of the ckt being sized for the specific load.

Don't know about that last one.
 
MAC702 said:
A duplex receptacle is no different than two simplex receptacles, so in either case you have more than one receptacle on the ckt.

We also allow a 50A device on a 30 or 40A ckt, very commonly seen with ranges and welding machines, so they can use the most common device for that type of equipment, regardless of the ckt being sized for the specific load.

Don't know about that last one.
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Correct, a duplex is two simplex receptacles, but the way the code reads is that you can have a duplex 15A receptacle on a 20A circuit, but not a simplex 15A on a 20A circuit. Just trying to understand why.
 
augie47 said:
AS far as the 180va question, note 220.14(I) where the 180va is mentioned states "except as covered in 220.14(J) for dwelling units where the 180va is not included.
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Yes agreed, residential applications are different. But in a commercial application it seems like you'd still be required to use 180VA at a minimum per 220.14(K) and (L) to determine the quantity of branch circuits you need.
 
shespuzzling said:
But in a commercial application it seems like you'd still be required to use 180VA at a minimum per 220.14(K) and (L) to determine the quantity of branch circuits you need.
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Query:
If you place any one receptacle on its own circuit, or even several, are you saying that an additional circuit(s) must be provided for it/them?
 
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