#14 Cu on a 100A breaker

I am not sure how you get that?

430.62(A) A feeder supplying a specific fixed motor
load(s) and consisting of conductor sizes in accordance with 430.24
shall be provided with a protective device having a rating
or setting not greater than the largest rating or setting of the
branch-circuit short-circuit and ground-fault protective device
for any motor supplied by the feeder [based on the maximum
permitted value for the specific type of a protective device in
accordance with 430.52, or 440.22(A) for hermetic refrigerant
motor-compressors], plus the sum of the full-load currents of
the other motors of the group.


The high-level object is a "feeder"
"supplying a" is inclusive, not exclusive.
Then referencing "430.24 Several Motors or a Motor(s) and Other Load(s) ", is a inclusive relative clause since 430.24 is included this "feeder" might carry more than just motors.
Then the terms "specific" and "fixed" are adjectives that function as prenominal modifiers for the noun "motor." not the feeder it can really be any feeder that supplies a fixed motor.
I don't see how you can read 430.62(A) as supplying anything other than motor loads. The language is very specific as feeder is modified by "supplying a specific fixed motor load(s).
If that is what it was intended to mean there would be no reason for 430.63 to exist.
 
In legal and code interpretation, the title of a section cannot limit the plain meaning of the text. See Trainmen v. Baltimore & Ohio R. Co. (1947)
"The title of a statute and the heading of a section cannot limit the plain meaning of the text.
While Wayne referenced the title of the sections, that specific language also appears in the text of the two sections, so you are not using the title for anything other the the ease of finding the rule when you are looking at the code.
430.62(A) A feeder supplying a specific fixed motor load(s) ....
430.63 Where a feeder supplies a motor load and other load(s), ...
 
I don't see how you can read 430.62(A) as supplying anything other than motor loads. The language is very specific as feeder is modified by "supplying a specific fixed motor load(s).
If that is what it was intended to mean there would be no reason for 430.63 to exist.
Just because a rule defines a requirement for a specific item (a motor), it does not exclude all other items (other loads).
See the article 100 definition of feeder, the way I read it is the topic of this section is a "feeder" and is unmodified by the words "specific" and "fixed" those are adjectives that function as prenominal modifiers for the noun "motor."
 
Just because a rule defines a requirement for a specific item (a motor), it does not exclude all other items (other loads).
Look, in context, comparing 430.62 with 430.63 makes it clear that 430.62 applies only when the "specifc fixed motor load(s)" are the only load(s). As 430.63 covers the other case. To argue otherwise based on wording minutiae is to be legalistically obstinate.

Cheers, Wayne
 
Just because a rule defines a requirement for a specific item (a motor), it does not exclude all other items (other loads).
Also, your interpretation gives a nonsensical result for a feeder that supplies both motors and non-motors.

430.24 says you can size the conductors according to the total load, motors and non-motors.
430.62 if it applies would say that accordingly the maximum OCPD size would be based only on the motor load, ignoring the non-motor load.
430.63 in its present form then says that the minimum OCPD size is again based on the total load.

Then with sufficient non-motor load on the feeder, 430.62 would give you a maximum size OCPD smaller than the minimum OCPD size that 430.63 gives you. A contradiction.

Cheers, Wayne
 
Wouldn't this logic then say all of the MV requirements should also apply to LV items?
The Supreme Court has long recognized that a section title cannot limit otherwise plain operative text. Bhd. of R.R. Trainmen v. Balt. & Ohio R.R. Co., 331 U.S. 519, 528-29 (1947) is the often cited refrence. There are some interesting law review articles on the topic
"feeder" is a defined term in Article 100, and the sentence itself does not restrict or redefine that term it only modified motors. Accordingly, if the text applies to feeders, the title alone should not be used to create a limitation that the operative language does not express, this is not the case with over 1000V sections that i am aware of.
There is the first sentence of 430.62(A) explicitly includes feeders "consisting of conductor sizes based on 430.24." it does not go onto modify that with a qualifier either.
If a rule says: "A box of apples cannot weigh more than 10 lbs," you can't say, "Well, I put a banana in here, so now it's a 'mixed fruit box' and the 10 lb limit doesn't count anymore."
The words "supplying a specific fixed motor" are just a packing list for what is inside the box.
In English, when you describe whats is in a box, you don't change the name of the box.

If you have a "Box of Apples," and you put a "Banana" in it, it is still a "Box of Apples."
The Topic (The Box) is the Feeder.
The Contents (The Apples) is the Motor.
The Extra Stuff (The Banana) is other loads.
 
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section title cannot limit otherwise plain operative text.
What part of my logic question involved titles? Your point seems to be no adjectives may ever be used as modifiers to the article 100 definitions.

So then what is needed to limit a requirement to a specific condition?
In post 42, Don provides clarifying text from the sections themselves, aren't these sufficient?
 
What part of my logic question involved titles? Your point seems to be no adjectives may ever be used as modifiers to the article 100 definitions.

So then what is needed to limit a requirement to a specific condition?
In post 42, Don provides clarifying text from the sections themselves, aren't these sufficient?
No not the way I read it, It does not address what I said in post #37 "specific" and "fixed" are adjectives that modifies for the noun "motor." not the feeder, the feeder is unmodified as defined in article 100.
 
430.62 if it applies would say that accordingly the maximum OCPD size would be based only on the motor load, ignoring the non-motor load.
430.63 in its present form then says that the minimum OCPD size is again based on the total load.
yes thats the way it reads to me, 430.63 is the "floor" and 430.62(A) is the "ceiling" there is no conflict there, saying you could technically put a 100A OCPD on #14 wire simply by adding a 1/2W light bulb, I would argue is an "Absurd Result", Since the primary purpose of the NEC is the "practical safeguarding of persons and property" (NEC 90.1), any interpretation that results in a fire-starting condition I would say is a "legal absurdity."
 
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No not the way I read it, It does not address what I said in post #37 "specific" and "fixed" are adjectives that modifies for the noun "motor." not the feeder, the feeder is unmodified as defined in article 100.
Yes, in430.62(A) "specific" and "fixed" are adjectives for motor. But the entire set of words "specific and fixed motor load" is also an adjective phrase to the noun "feeder".
 
Yes, in430.62(A) "specific" and "fixed" are adjectives for motor. But the entire set of words "specific and fixed motor load" is also an adjective phrase to the noun "feeder".
For example say you have a rule "A box of specific red apples shall be loaded to no more than 10lbs"
In English, adding extra items doesn't "un-describe" the first item.
If you add a banana to that box, is it still a "box of specific red apples" ?
Here is a truth table for 430.62(A):
Is it a Feeder?​
Has a Specific Motor?​
Has a Fixed Motor?​
Has "Other Load"?​
430.62(A) Applies?
1​
1​
1​
0​
1
1​
1​
1​
1​
1
0​
1​
1​
1​
0
1​
1​
0​
1​
0
1​
0​
1​
1​
0
 
For example say you have a rule "A box of specific red apples shall be loaded to no more than 10lbs"
In English, adding extra items doesn't "un-describe" the first item.
If you add a banana to that box, is it still a "box of specific red apples" ?
Here is a truth table for 430.62(A):
Is it a Feeder?​
Has a Specific Motor?​
Has a Fixed Motor?​
Has "Other Load"?​
430.62(A) Applies?
1​
1​
1​
0​
1
1​
1​
1​
1​
1
0​
1​
1​
1​
0
1​
1​
0​
1​
0
1​
0​
1​
1​
0
You table is only valid using your assumption that adjectival phrases are meaningless.
 
You table is only valid using your assumption that adjectival phrases are meaningless.
You did not answer the question
For example say you have a rule "A box of specific red apples shall be loaded to no more than 10lbs"
In English, adding extra items doesn't "un-describe" the first item.
If you add a banana to that box, is it still a "box of specific red apples" ?
 
yes thats the way it reads to me, 430.63 is the "floor" and 430.62(A) is the "ceiling" there is no conflict there
OK, let's think through an example of this interpretation. Say we have a feeder supplying 150A of non-continuous non-motor loads, and a 40A FLC motor load. A very realistic example. The motor branch circuit is protected downstream with a 100A inverse time breaker, allowing the motor to start fine, so neither of the exceptions to 430.52(C) apply.

(a) 430.24 says the feeder conductors must have an ampacity of at least 200A. We'll choose 3/0 Cu with 90C insulation, 75C ampacity 200A.
(b) If it applied, 430.62 would say that the feeder OCPD must be at most 100A. There's no mention of non-motor loads in the 430.62 computation.
(c) 430.63 (with its current error, IMO) says that the feeder OCPD must be at least 250A.

Given (a), how does (b) make sense? It doesn't, a 100A OCPD would be less than the non-motor load and would violate 215.3 even if the motor weren't there. So we realize that 430.62 doesn't apply.

And now where is the maximum OCPD for the 3/0 Cu conductors specified? It isn't, because (c) is a mistake. 430.63 should instead say that the feeder OCPD for 3/0 Cu conductors must be at most 250A in this example.

Cheers, Wayne
 
Actually the extra items clarify the first item, that is the purpose of an adjectival phrase.
An adjective phrase identifies the subject. If I say, "The man in the red hat is tall," and that man is also wearing a blue scarf, he is still the "man in the red hat." The scarf doesn't make the "red hat" description false
 
An adjective phrase identifies the subject.
Rather than debating linguistics, why don't you tell me how you understand the NEC tells you to size the conductors and OCPD for the feeder in my last example (post #56)? With reference to all applicable NEC sections, which will include at a minimum 430.24 and 430 Part V.

Cheers, Wayne
 
OK, let's think through an example of this interpretation. Say we have a feeder supplying 150A of non-continuous non-motor loads, and a 40A FLC motor load. A very realistic example. The motor branch circuit is protected downstream with a 100A inverse time breaker, allowing the motor to start fine, so neither of the exceptions to 430.52(C) apply.

(a) 430.24 says the feeder conductors must have an ampacity of at least 200A. We'll choose 3/0 Cu with 90C insulation, 75C ampacity 200A.
(b) If it applied, 430.62 would say that the feeder OCPD must be at most 100A. There's no mention of non-motor loads in the 430.62 computation.
(c) 430.63 (with its current error, IMO) says that the feeder OCPD must be at least 250A.

Given (a), how does (b) make sense? It doesn't, a 100A OCPD would be less than the non-motor load and would violate 215.3 even if the motor weren't there. So we realize that 430.62 doesn't apply.

And now where is the maximum OCPD for the 3/0 Cu conductors specified? It isn't, because (c) is a mistake. 430.63 should instead say that the feeder OCPD for 3/0 Cu conductors must be at most 250A in this example.

Cheers, Wayne
(a) 430.24 says the feeder conductors must have an ampacity of at least 200A.
(b) 430.62 has options A and B
(A) would say that the feeder OCPD must be at most 100A.
430.62(B) Can apply where feeder conductors have an
ampacity greater than required by 430.24.
We'll choose 4/0 Cu with 90C insulation, 75C ampacity 230A now 430.62(B) Can apply.

(c) 430.63 says that the feeder OCPD must be at least 250A.
QED
 
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