Ask Experts Questions for FREE Help !
Ask

Computation of load for convenience outlet

Asked Sep 17, 2008, 10:02 PM — 1 Answer
I just want to be sure in my computation. The national electrical code provides that, "for each single receptacle shall be considered at no less than 180 watts rating". For me its mean that each convenience outlet is considered to have a maximum load of not less than 180 watts per plug or gang.

If I have 6 convenience receptacles, considering that the there are two plug per outlet, the total number of plug will be: 6 outlets x 2 plug = 12 pieces

The total estimated Load: 12 x 180 watts per outlet = 2,160 watts

The maximum Expected Current Load: 2,160 watts / 230 watts = 9.39 amperes.

In my computation I am right or not ,if not could give some explanation.

1 Answer
stanfortyman's Avatar
stanfortyman Posts: 4,882, Reputation: 1326
Electrical & Lighting Expert
 
#2

Sep 18, 2008, 03:41 AM


This is what is wrong with lay folks trying to read the ever confusing NEC. There is usually way more than meets the eye.
It is also a problem with books that reference the NEC. Many times important information is either misinterpreted or left out all together.

First off:

220.14(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).


See the each yoke comment above. That means a duplex is counted the same as a simplex receptacle. A duplex is NOT two for purposes of this calculation.





Second, and even more important, none of this applies to dwelling units or residences. So you can pretty much forget 220.14(I) all together for residential work:

220.14(J) Dwelling Occupancies 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)



Helpful

Not your question? Ask your question View similar questions

 
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Add your answer here.

Remove Text Formatting

Undo
Redo
 
Decrease Size
Increase Size
Bold
Italic
Underline
Align Left
Align Center
Align Right
Ordered List
Unordered List
Decrease Indent
Increase Indent
Insert Email Link
Wrap [QUOTE] tags around selected text
Wrap [CODE] tags around selected text
Wrap [HTML] tags around selected text
Wrap [PHP] tags around selected text
Wrap [YOUTUBE] tags around selected text
Notification Type:



Check out some similar questions!

Convenience outlet [ 2 Answers ]

Hi there. I live in an old apartment building and I have fuses in my apartment. My bathroom vanity light has the outlet attached to it. And my electrician says I need to replace the fuse box with circuit breakers run a wiremold into my bathroom to create a new outlet. I was wondering 1st does...

15 amp outlet on 20 amp circuit and load [ 7 Answers ]

Hi, I have a 20A circuit that currently has 15A outlets on it. Currently, only my fridge (11.5A) and another outlet is on this circuit. Q1: If I connect 15A outlets in a series with 12/2, does that effectively lower the rating of the rest circuit to 15A? Can I wire in this as this example...

Replacing vanity light without a convenience outlet [ 1 Answers ]

I want to replace a 35-yr old bath vanity light with attached convenience outlet, with one that does not have an outlet. My electrical experience is limited to replacing simple fixtures. What should I look out for when I remove the old light, and what should I do with the outlet wire? Thanks much,...

Keep it alive for Convenience? [ 7 Answers ]

My live-in boyfriend of 21 years, decided to cheat on me with a woman (for 3 months now) while I was going over a terrible depression due to my brother's murder (in another state), problems with tenants, and my job becoming shaky. I really needed him and he turned to someone else for attention...


View more Electrical & Lighting questions Search