"free conductor"

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augie47

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Tennessee
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O.K, all you test takers...... I hate when, as an inspector, I can't answer a Code question, but this SIMPLE one has stumped me.
As it was relayed to me: "In a 12 x 12 j box where the grounded conductor is spliced, how much 'free conductor' is required?"
I think the answer is in 300.14.
At first read it says 6" of free conductor measure from the point in the box where it emerges, but that would give you 6 + 6 and not even enough to splice.
Someone teach me how to read or give me a better reference.
 

chris kennedy

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Miami Fla.
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60 yr old tool twisting electrician
There is no such thing as a free conductor, they all cost money. Did you look at NECHB Exhibit 300.13?
 

charlie b

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Lockport, IL
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Someone teach me how to read. . . .
You are reading it correctly. You are just trying to read what is not there. ;)

. . . but that would give you 6 + 6 . . .
See. You do know how to read. You have that answer right: The answer is a total of 12. :)

. . . and not even enough to splice.
So what? The NEC is not a design manual. It is a minimum for safety. If you have to do more than the minimum, in order to complete a job, then so be it. :roll:
 

chris kennedy

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Location
Miami Fla.
Occupation
60 yr old tool twisting electrician
At first read it says 6" of free conductor measure from the point in the box where it emerges, but that would give you 6 + 6 and not even enough to splice.

See. You do know how to read. You have that answer right: The answer is a total of 12. :)

Read again, the answer is 6.

300.14 Length of Free Conductors at Outlets, Junctions, and Switch Points.

At least 150 mm (6 in.) of free conductor, measured from the point in the box where it emerges from its raceway or cable sheath, shall be left at each outlet, junction, and switch point for splices or the connection of luminaires or devices. Where the opening to an outlet, junction, or switch point is less than 200 mm (8 in.) in any dimension, each conductor shall be long enough to extend at least 75 mm (3 in.) outside the opening.

Exception: Conductors that are not spliced or terminated at the outlet, junction, or switch point shall not be required to comply with 300.14.
 

chris kennedy

Senior Member
Location
Miami Fla.
Occupation
60 yr old tool twisting electrician
Read the question again.Since the question speaks of a splice, we must infer there are two or more wires involved. So each wire needs 6 inches, and the total is a minimum of 12.:D

I see, reading comprehension, a novel idea indeed.
 

iwire

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Location
Massachusetts
What does 'free conductor' really mean?

Q. We cut our wire too short in a few outlet boxes so I spliced on a couple inches of conductor so that I had the required 6 in. of free conductor at each location. The inspector says the free conductor must be "unspliced." Is he right?

A. No. He is correct that the NEC requires at least 6 in. of free conductor be available from the point in the box where the conductors enter the enclosure [300.14]. However, nowhere in this rule does it require that the free length of conductor be unspliced.

http://ecmweb.com/nec/code_qa/stumped-by-nec-code-20090801/
 
the code doesn't say you cant splice a four inch wire onto a two inch wire(for example). it just says you need 6 inches, so why would you assume you need six inches and then six more inches? you need 6 inches of free condutor, it does not stop you from spliceing to make the total of 6 inches only.
 

charlie b

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I think the original question had to do with a six inch wire coming from the left conduit, and a six inch wire coming from the right conduit, totalling 12 inches of wire, in a box that is 12 inches wide, so that the two wires might be able to touch each other, but could not be actually connected to each other.
 

btharmy

Senior Member
Location
Indiana
I read the 6" minimum is per conductor. Each individual conductor entering a box whether from a cable or conduit must be at least 6in long. I have seen a contractor take this to the literal extreme and land his branch circuit mc cables into the top of a 24"x24"x6" jbox mounted on the precast 30ft above a panel. The wires inside the box were all cut about 6 to 8in long. None of the neutrals or grounds reach each other. Completely silly install. It is a minimum. Mine were all 24" long plenty of wire to make joints etc....
 
Typically test questions are not tricky. They are designed to see of one is aware of and understands code requirements.

There was not stipulation in the question about different entry locations. All it mentioned was there are splices (the splice could be conductors from the same cable or conduit). Splices are part of the requirement where 6 inches is the minimum. Hence the answer to this question is 6 inches.
 

roger3829

Senior Member
Location
Torrington, CT
the code doesn't say you cant splice a four inch wire onto a two inch wire(for example). it just says you need 6 inches, so why would you assume you need six inches and then six more inches? you need 6 inches of free condutor, it does not stop you from spliceing to make the total of 6 inches only.

Quote:
300.14 Length of Free Conductors at Outlets, Junctions, and Switch Points.

At least 150 mm (6 in.) of free conductor, measured from the point in the box where it emerges from its raceway or cable sheath, shall be left at each outlet, junction, and switch point for splices or the connection of luminaires or devices. Where the opening to an outlet, junction, or switch point is less than 200 mm (8 in.) in any dimension, each conductor shall be long enough to extend at least 75 mm (3 in.) outside the opening.

?? If the conductor enters a box and only extends in 4" it is too short according to the code. It doesn't say that you can splice a piece of another conductor to the original conductor to make it be the correct length. That's the whole point of having 6" of free conductor so that it can be terminated outside of the box.
 
Quote:
300.14 Length of Free Conductors at Outlets, Junctions, and Switch Points.

At least 150 mm (6 in.) of free conductor, measured from the point in the box where it emerges from its raceway or cable sheath, shall be left at each outlet, junction, and switch point for splices or the connection of luminaires or devices. Where the opening to an outlet, junction, or switch point is less than 200 mm (8 in.) in any dimension, each conductor shall be long enough to extend at least 75 mm (3 in.) outside the opening.

?? If the conductor enters a box and only extends in 4" it is too short according to the code. It doesn't say that you can splice a piece of another conductor to the original conductor to make it be the correct length. That's the whole point of having 6" of free conductor so that it can be terminated outside of the box.


I have 3 points 1) show me where it says they can't be spliced??
2) I'm not the only one with this understanding
(read the post above mine written while I was
posting.) so why in the world would you
qoute me???
3) define "free" if you spliced 2 inches onto 4
inches why is this not "free" this is trade
school 101 - im still young enough to remember.
 

charlie b

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Lockport, IL
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Retired Electrical Engineer
I have not seen anything that tells me that anyone would object to splicing a 2 inch wire to a 4 inch wire, and thus achieving 6 inches of free conductor.
 

One-eyed Jack

Senior Member
Typically test questions are not tricky. They are designed to see of one is aware of and understands code requirements.

There was not stipulation in the question about different entry locations. All it mentioned was there are splices (the splice could be conductors from the same cable or conduit). Splices are part of the requirement where 6 inches is the minimum. Hence the answer to this question is 6 inches.

If the tester does not provide All of the pertinent information they have no reason to expect a correct answer. Your example assumes a splice in the conductors from the same cable or conduit. This could very well be true but is not stipulated. For practical reasons it would be better to say 12 inches. Sometimes the testors don't live in the real world.
 
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