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jumper said:
I totally know what you meant and that you were not being flippant on the subject.

It is just that I am way too sensitive to how it is used in casual conversation.

I get more upset than I should, but I am a historian at heart.

So, do not take my over blown out burst to heart.

I know you are a good man Charlie Brown.
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History was one of my worst subjects in school, I really didn't like it at all.

Now the world as I knew it in school is actually in the history books.

History means much more to me now, and is much more interesting. I love the way it changes all the time, too. :huh:
 
electrofelon said:
What about 210.11 (A)?
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210.11 is all about number of branch circuits needed, not about a max number of recpts that can be on a circuit.

It's the same with track lighting, you figure your load calc based on the number of feet of track you have, but when you get to your branch circuit you could put 500' of track on one 15A breaker if you only have a couple of track heads on that run.
 
electrofelon said:
Doesn't it say ".....as calculated in 220"?
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Number of Branch Circuits. The minimum number of branch circuits shall be determined from the total calcu- lated load and the size or rating of the circuits used. In all installations, the number of circuits shall be sufficient to supply the load served. In no case shall the load on any circuit exceed the maximum specified by 220.18.

What is the load of a circuit with nothing plugged into the receptacles?

A receptacle with no connected load draws not much power IIRC.:D
 
jumper said:
This whole argument would be easily solved if the CMP read Charlie’s Rule and changed the wording properly to reflect their intent.
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The whole argument would be easily solved it the hand wringers would catch on to the fact that a recept with nothing plugged into it is not going to overload a circuit and stop worrying about a max number of recepts on one circuit.
 
ActionDave said:
The whole argument would be easily solved it the hand wringers would catch on to the fact that a recept with nothing plugged into it is not going to overload a circuit and stop worrying about a max number of recepts on one circuit.
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For myself, I truly believe that the code “intends” us to do do the 220.18 thing and limit the amount of receptacles as that MH page did earlier, but the actual wording does not properly carry out that interpretation or intent IMO, so I carry on about it till it is fixed.
 
jumper said:
I did comply. I calculated my total branch circuit load according to 220.

But 210.19 or 210.21 say nada about adding up receptacles.
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Again:

2014 NEC
210.2 Other Articles for specific-purpose branch circuits.
Branch circuits shall comply with this article and also applicable provisions of other articles of this code.

That's as far as I needed to go in Art. 210

Again:

By Mike Holt, for EC&M Magazine



Q1 What is the maximum number of 15 or 20A, 125V receptacle outlets permitted on a 20A, 120V general-purpose branch circuit in a commercial occupancy?



A1 For commercial occupancies, the NEC requires each receptacle outlet to be calculated at 180 VA [220.14(I)]. Therefore, the maximum number on a 20A circuit would be 13.
Circuit VA = Volts x Amperes
Circuit VA = 120V x 20A
Circuit VA = 2,400 VA
Number of Receptacles = 2,400 VA/180 VA
Number of Receptacles = 13



Note: According to the NEC Handbook, published by the NFPA, general-purpose receptacles aren't considered a continuous load.


And the number is? 13


​
Plain and simple, 220.14 (I) tells you how to calc the maximum number of receptacles that can be installed on a 20 amp or less General-Purpose branch circuit in a non dwelling occupancy.

If you read 220.14 (J) (1) & (2) there is no limit on the number of receptacles that can be installed on a General Purpose 15 or 20 amp branch circuit. You can install a 100 15A duplex receptacles on a 15 amp General-Purpose branch circuit if you want.

Period.

IF Mike Holt, one of the contributors to writing the NEC, says 13 is the maximum allowed on a 20 amp General-Purpose non dwelling occupancy branch circuit that is good enough for me.:happyyes:

If you were asking for a ruling, he would be one of the people you could ask.

Best regards,
Jim
 
Jamesco said:
Again:

IF Mike Holt, one of the contributors to writing the NEC, says 13 is the maximum allowed on a 20 amp General-Purpose non dwelling occupancy branch circuit that is good enough for me.:happyyes:

If you were asking for a ruling, he would be one of the people you could ask.

Best regards,
Jim
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Mike Holt is not on code making panel No. 2 which is responsible for Articles 210 and 220.
 
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Jamesco said:
Plain and simple, 220.14 (I) tells you how to calc the maximum number of receptacles that can be installed on a 20 amp or less General-Purpose branch circuit in a non dwelling occupancy.
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No, it doesn't. 220.14 doesn't say anything about receptacle installations, just load calculations. 220.14 and 220.14(I) both specify minimums, not maximums. To wit:
220.14 Other Loads — All Occupancies. In all occupancies, the minimum load for each outlet for general-use receptacles and outlets not used for general illumination shall not be less than that calculated in 220.14(A) through (L), the loads shown being based on nominal branch-circuit voltages.

(A) Specific Appliances or Loads. An outlet for a specific appliance or other load not covered in 220.14(B) through (L) shall be calculated based on the ampere rating of the appliance or load served.

(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.
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Calculation minimums, nothing about installation maximums.
 
LarryFine said:
No, it doesn't. 220.14 doesn't say anything about receptacle installations, just load calculations. 220.14 and 220.14(I) both specify minimums, not maximums. To wit:


Calculation minimums, nothing about installation maximums.
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Larry,

We both agree that 220.14(I) is for calculating the minimum load for receptacles connected to a general purpose branch circuit in a commercial occupancy. Agree?

Where we disagree ,you say 220.14(I) has nothing to do with the number of receptacles that are connected to the branch circuit. Therein, the maximum number of receptacles. You say there is no limit to how many receptacles can be connected to the branch circuit.

Lets say you have 30 duplex receptacles. For calculating the total load for the 30 duplex receptacles you multiply 30 X 180VA = 5400VA.
That is the total calculated load for the 30 duplex receptacles. Would you agree?

If the total calculated load is 5400VA, per code, can you connect the 30 duplex receptacles to a 2400VA (120V X 20 amp)20 amp branch circuit? If yes, please explain. Please Site the NEC Article where it says you can.

Jim
 
Jamesco said:
Larry,

We both agree that 220.14(I) is for calculating the minimum load for receptacles connected to a general purpose branch circuit in a commercial occupancy. Agree?
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Yes, as far as sizing the service for the premises, that is the minimum .

Where we disagree ,you say 220.14(I) has nothing to do with the number of receptacles that are connected to the branch circuit. Therein, the maximum number of receptacles. You say there is no limit to how many receptacles can be connected to the branch circuit.
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Agreed. 220.14(I) certainly does not specify a quantity of receptacles.

Lets say you have 30 duplex receptacles. For calculating the total load for the 30 duplex receptacles you multiply 30 X 180VA = 5400VA.
That is the total calculated load for the 30 duplex receptacles. Would you agree?
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Yes, as far as the allowance for the service sizing is concerned. So far, no power is being consumed.

If the total calculated load is 5400VA, per code, can you connect the 30 duplex receptacles to a 2400VA (120V X 20 amp)20 amp branch circuit?
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Yes, because this has nothing to do with the service calculation. Receptacles are not loads.

What do you do if you installed those 13 receptacles on one circuit, and then plug in 13 16-amp loads?

If yes, please explain. Please Site the NEC Article where it says you can.
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(That's "cite") As has been pointed out many times, the NEC generally prohibits, rather than allows.

You're saying that the minimum allowance for load calculations are also binding on actual installation.

I'm saying that actual usage is what matters for installation. Some circuits get only one receptacle.

220.14(I) doesn't restrict us to 1 receptacle for a large load, nor 13 receptacles for minimal loads.
 
jumper said:
The 5400VA would be divided by circuit VA for minimum of circuits, which is 3, but nothing says how many receptacles per circuit.
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Technically speaking, even the 3 circuits isn't mandated as far as actual installation is concerned.

If I were installing a circuit to supply, say, 30 USB chargers, I wouldn't hesitate to use one circuit.
 
James,

If the calculated load per 220 is 180VA per receptacle, then is the receptacle limited to 180VA installed?

That means no using any receptacle for a load over 1.5A. Think about it. Does that make sense?
 
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