20 amp circuits

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Mike does make a good point--if your individual branch circuit has only a single receptacle, then it is subject only to 210.21(B)(1), while if it has multiple receptacles, it is subject to 210.21(B)(2) and 210.21(B)(3).

So if I understand correctly, then a piece of equipment could have a rating of 120V/15A (non-continuous) with a NEMA 5-15 cord cap and call for an individual branch circuit. If you install a single 15 amp receptacle on a 15 amp individual branch circuit to serve the equipment, that would comply with 210.21(B)(1). But if you used a duplex receptacle, the installation would now violate 210.21(B)(2).

Other examples like this exist. The way 210.21(B) is written seems to imply that an individual branch circuit will have only one receptacle, even though the definition doesn't require that, and even though there are sometimes good design reasons to have more than one receptacle on an individual branch circuit. The disparity between the Article 100 definition of individual branch circuit and the way 210.21(B) is written probably is the cause of alot of the confusion on this thread.

Cheers, Wane
 
210.21(B) places restrictions on the receptacle rating depending on if you have one or more recpetacles on a indi-bc. am i correct?

one 20A single on a 15A indi-bc, is ok for nec ????
one 15A single on a 20A indi-bc, not ok for nec
one 15A duplex on a 20A indi-bc, ???????? <--- to me, this should not be allowed, duplex should be 20A rated

explain this figure, seems to suggest the 15A duplex (probably includes single too) is ok ONLY IF ITS ON A MULTI-OUTLET BC (i mean look, they highlight it in red). to me, the art-100 definition of indi-bc really ties the bc to "single outlet". what you put into that outlet is an allowed variable within NEC restrictions, etc.

besides art-100 def of indi-bc, all of the figures and verbiage seem to support the notion that a indi-bc is really a bc that has a single outlet.

102ecmCBfig1.jpg



In accordance with Section 210.21(B)(1), If a single receptacle is installed on a branch circuit, it
shall have an ampere rating of not less than that of the branch circuit.
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One single receptacle: A branch circuit with one single receptacle and no other
receptacles must use a NEMA 5-20R receptacle.
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this is a tad wonky. a 15A single receptacle BC can have a 20A rated recept?? doesnt seem right. a BC that has one and only one receptacle should have a receptacle that is rated to match the BC rating. why? because a 20A rated recept is physically different and would allow a 20A cord cap to plug in !!
 
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The amp rating of the receptacles allowed to be on a 15 or 20A circuit is not under discussion. What is under discussion is the number of receptacles allowed on an individual branch circuit by code. By code there is not any limit on the number of receptacles on an individual branch circuit. Nothing in 210.21 or the rest of the nec or even Mike Holt himself can change that fact.
 
wwhitney said:
Mike does make a good point--if your individual branch circuit has only a single receptacle, then it is subject only to 210.21(B)(1), while if it has multiple receptacles, it is subject to 210.21(B)(2) and 210.21(B)(3).

So if I understand correctly, then a piece of equipment could have a rating of 120V/15A (non-continuous) with a NEMA 5-15 cord cap and call for an individual branch circuit. If you install a single 15 amp receptacle on a 15 amp individual branch circuit to serve the equipment, that would comply with 210.21(B)(1). But if you used a duplex receptacle, the installation would now violate 210.21(B)(2).

Other examples like this exist. The way 210.21(B) is written seems to imply that an individual branch circuit will have only one receptacle, even though the definition doesn't require that, and even though there are sometimes good design reasons to have more than one receptacle on an individual branch circuit. The disparity between the Article 100 definition of individual branch circuit and the way 210.21(B) is written probably is the cause of alot of the confusion on this thread.

Cheers, Wane
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Boy are we opening a huge can of worms here and I don't know if I have the ambition for it.:D

Those sections are a mess, 99.99% of the time the manufacturer chooses the plug and they may not follow the limitations found in the NEC.

Those sections seem to assume the average user of electricity is aware of the rules, aware of what receptacles are connected to what circuits, what the ratings of those circuits are and have a running total of the connected load in their head before they plug anything in.
 
ActionDave said:
The amp rating of the receptacles allowed to be on a 15 or 20A circuit is not under discussion. What is under discussion is the number of receptacles allowed on an individual branch circuit by code. By code there is not any limit on the number of receptacles on an individual branch circuit. Nothing in 210.21 or the rest of the nec or even Mike Holt himself can change that fact.
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yes, that is part of the argument. but look around at the verbiage in these various sections. they use the word "multioutlet" and "outlet" quite often. now when you go read art-100 def for indi-bc the intention seems obvious. as others have stated, "indi-bc" has typically been interpreted to mean "dedicated" (nec does not use that word), and that dedication is to some piece of equipment, BUT, as many have said, having more than a single receptacle is not a violation, but in context of the intent of "indi-bc" as defined in art-100 i believe the intention was to define the bc as a single outlet bc. otherwise, i could install gp-bc's and label them "dedicated" for inspection, save myself a bunch of ocpd's ??

if art-100 definition changed to say "a bc that has only one Outlet" would that goof up any other part of nec? i say no, and would actually accurately define the purpose (intent) of having a indi-bc, etc.
 
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FionaZuppa said:
now when you go read art-100 def for indi-bc the intention seems obvious. as others have stated, "indi-bc" has typically been interpreted to mean "dedicated" (nec does not use that word), and that dedication is to some piece of equipment, BUT, as many have said, having more than a single receptacle is not a violation, but in context of the intent of "indi-bc" as defined in art-100 i believe the intention was to define the bc as a single outlet bc. .
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And there lies the problem, you are absoulutly locked into the belief your opinion of the intent is correct when neither the words in the definition nor the words of the CMP support your viewpoint of the intent.
 
iwire said:
And there lies the problem, you are absoulutly locked into the belief your opinion of the intent is correct when neither the words in the definition nor the words of the CMP support your viewpoint of the intent.
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yikes. i suspect the intention did not translate properly into verbiage that we see today in the codebook.

i wire up a gp-bc, inspector comes and he says "what's that for", and i say its a indi-bc for my 14A wall mounted garage vac that i may move around during the year. he says "no, you cant have outlets all over the place like that for a bc that feeds only your 14A vac, you need a individual branch circuit that has single receptacle for your vac", i call out the NEC art-100 definition and code sections and show that i am right per nec, but he then scratches his head and wonders why the art-100 definition for indi-bc is there in the 1st place.

i mean look, ask 1,000 inspectors what they think "indi-bc" means, or is meant to mean, because after-all, inspectors interpret the nec verbiage and derive to conclusions via meant-to-mean use of the knoggin. many many times their conclusions are based on commonality of interpretations between professionals, sometimes a rare scenario will need a confirmation/clarification by one other person they work with (which can be way off from commonality views).
 
FionaZuppa said:
yikes. i suspect the intention did not translate properly into verbiage that we see today in the codebook.

i wire up a gp-bc, inspector comes and he says "what's that for", and i say its a indi-bc for my 14A wall mounted garage vac that i may move around during the year. he says "no, you cant have outlets all over the place like that for a bc that feeds only your 14A vac, you need a individual branch circuit that has single receptacle for your vac", i call out the NEC art-100 definition and code sections and show that i am right per nec, but he then scratches his head and wonders why the art-100 definition for indi-bc is there in the 1st place.

i mean look, ask 1,000 inspectors what they think "indi-bc" means, or is meant to mean, because after-all, inspectors interpret the nec verbiage and derive to conclusions via meant-to-mean use of the knoggin. many many times their conclusions are based on commonality of interpretations between professionals, sometimes a rare scenario will need a confirmation/clarification by one other person they work with (which can be way off from commonality views).
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I get it, you know the intent is something other than the code or the code writers say it is. :D
 
iwire said:
I get it, you know the intent is something other than the code or the code writers say it is. :D
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no, i said that is what i believe the issue at hand is. perhaps i am dead wrong. but in looking at various verbiage of various sections of nec, with the art-100 definitions, to me it makes perfect sense that a indi-bc is a bc that has special restrictions on termination, namely single outlet, and, the use of words in that definition to describe what is attached doesnt make a lot of sense given the other definitions of bc's, and the fact that the words "utilization equipment" already exist in the art-100 definition for "Outlet".

the above statement also agrees with you and others about the requirement (or lack of requirement) for single receptacle, but as i have stated it i do not reference the word "receptacle", etc.

not my 1st rodeo with code books :thumbsup:, nec needs some fixin' , etc.
 
FionaZuppa said:
yikes. i suspect the intention did not translate properly into verbiage that we see today in the codebook.

i wire up a gp-bc, inspector comes and he says "what's that for", and i say its a indi-bc for my 14A wall mounted garage vac that i may move around during the year. he says "no, you cant have outlets all over the place like that for a bc that feeds only your 14A vac, you need a individual branch circuit that has single receptacle for your vac", i call out the NEC art-100 definition and code sections and show that i am right per nec, but he then scratches his head and wonders why the art-100 definition for indi-bc is there in the 1st place.
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That inspector can have it explained to him that while the NEC does indeed recognize individual branch circuits, it does not require you to only have the single receptacle on the IB ckt feeding the single piece of equipment. And he can be told too that as far as any single rec requirement, the NEC 210.21(B)(1) only says that IF you decide to use only one receptacle on that IB ckt it must match the ampacity of the ckt, not that a single receptacle is required outright for the individual bc.

If someone can't understand that then too bad.

I don't get the confusion behind this- at least the code is allowing a little leeway in this instance by giving you options to feed equipment, instead of being unnecessarily strict.

You could maybe get legitimately nailed if the instructions that come with the equipment require a "dedicated ckt w/ no other outlets" or similiar phrasing- per the listing/labeling requirements in 110.3(B).



But a better less irritating idea to deal w/ an inspector if this ever came up, is to just not say anything.:D
 
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user 100 said:
That inspector can have it explained to him that while the NEC does indeed recognize individual branch circuits, it does not require you to only have the single receptacle on the IB ckt feeding the single piece of equipment. And he can be told too that as far as any single rec requirement, the NEC 210.21(B)(1) only says that IF you decide to use only one receptacle on that IB ckt it must match the ampacity of the ckt, not that a single receptacle is required outright for the individual bc.

If someone can't understand that then too bad.

I don't get the confusion behind this- at least the code is allowing a little leeway in this instance by giving you options to feed equipment, instead of being unnecessarily strict.

You could maybe get legitimately nailed if the instructions that come with the equipment require a "dedicated ckt w/ no other outlets" or similiar phrasing- per the listing/labeling requirements in 110.3(B).

But a better less irritating idea to deal w/ an inspector if this ever came up, is to just not say anything.:D
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ok, i get ya. under your explanation of it, whats the diff between gp-bc and indi-bc given my example?

my garage vac directions say to use a dedicated 20A circuit. ok, where in NEC do i find what it means to have a "dedicated circuit" ??

all that said, what exactly is the point of having the indi-bc definition if i can wire up a gp-bc ??
 
FionaZuppa said:
ok, i get ya. under your explanation of it, whats the diff between gp-bc and indi-bc given my example?

my garage vac directions say to use a dedicated 20A circuit. ok, where in NEC do i find what it means to have a "dedicated circuit" ??

all that said, what exactly is the point of having the indi-bc definition if i can wire up a gp-bc ??
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I suspect your question about the presence of the IBC in the code was answered here already:

Little Bill said:
I agree the wording of the code does not limit the number of receptacles on an individual branch circuit.

However, why even have individual branch circuits in the code? I don't see the difference between them and a general purpose branch circuit. How could one determine whether the circuit was GP or INV. BC if he was inspecting it? Or enforce anything about it?
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iwire said:
Because UL keeps requiring dedicated circuits for many kinds of equipment.
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As for the query about code citations/ info for a "dedicated ckt", earlier it was mentioned correctly that that was/is often slang- not code language- for IBC, so where do you think any info relating to a dedicated ckt would be found in the NEC?;)
 
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FionaZuppa said:
ok, i get ya. under your explanation of it, whats the diff between gp-bc and indi-bc given my example?
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An indi-bc is designed to supply only one piece of utilization equipment, possibly at multiple locations via multiple outlets on the indi-bc.

A gp-bc is designed to serve multiple, possibly unknown, pieces of utilization equipment.

Sure, an indi-bc with multiple outlets could be misused to serve multiple pieces of utilization equipment. So what? There's typically no safety issue. There are lots of things the NEC requires that the average end user of electricity may get wrong, we have managed to identify another one. :)

Cheers, Wayne
 
wwhitney said:
An indi-bc is designed to supply only one piece of utilization equipment, possibly at multiple locations via multiple outlets on the indi-bc.


Cheers, Wayne
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example please.
 
ritelec said:
???

not that I doubt, but I didn't think so.... can you reference that please


Thank you
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Here ya go.

210.21 Outlet Devices
Outlet devices shall have an ampere rating that is not less
than the load to be served and shall comply with 210.21(A)
and (B).
(A) Lampholders.......blah, blah blah.
(B) Receptacles.
(1) Single Receptacle on an Individual Branch Circuit.
A single receptacle installed on an individual branch circuit
shall have an ampere rating not less than that of the branch
circuit.
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Ok. Thank you for posting that.

Question.

Would it then be permissible to put a 30. or 40 or 50 amp receptacle on a 15 amp circuit ?
 
ritelec said:
Ok. Thank you for posting that.

Question.

Would it then be permissible to put a 30. or 40 or 50 amp receptacle on a 15 amp circuit ?
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Let me ask you this, where can I find a 40 amp receptacle?

What I am getting at is simply the fact that as we move up in ampacity the choices of receptacles slims down.

If you have a machine that needs a 70 amp circuit you will need to use a 100 amp receptacle for it because no one makes 70 amp receptacles. (That I know of)
 
Ok. Scrub the 40 and insert a 100 amp receptacle

:- )

Is it permissible to put a 100 amp receptacle in a 15 amp circuit?

Thank you.
 
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