Drill or not to drill

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ceb58

Senior Member
Location
Raeford, NC
Too tired to search. I have 3 - 14/3's and 1-14/2 in a bored hole that will be fire caulked. These 3 are travelers for 3-3way switches and a home run to a recpt.. So do I have 8 ccc or 11 ccc ? Cant remember if all of the conductors in the travelers have to be counted or just 2. Just need to know if I need to drill another hole
 

GoldDigger

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Staff member
Location
Placerville, CA, USA
Occupation
Retired PV System Designer
Too tired to search. I have 3 - 14/3's and 1-14/2 in a bored hole that will be fire caulked. These 3 are travelers for 3-3way switches and a home run to a recpt.. So do I have 8 ccc or 11 ccc ? Cant remember if all of the conductors in the travelers have to be counted or just 2. Just need to know if I need to drill another hole
Only one of the two travelers can be carrying current at one time. And if your third conductor in each switch leg is just a neutral to satisfy the requirement that the neutral be present in a switch box, rather than the neutral for the actual lighting load, it would not be current carrying either, at least not until someone modified the wiring and connected a larger load than a presence sensor to the box. But 8 is a good conservative number.
Some inspectors would have objections to using 5 in the calculation.
 

ceb58

Senior Member
Location
Raeford, NC
Only one of the two travelers can be carrying current at one time. And if your third conductor in each switch leg is just a neutral to satisfy the requirement that the neutral be present in a switch box, rather than the neutral for the actual lighting load, it would not be current carrying either, at least not until someone modified the wiring and connected a larger load than a presence sensor to the box. But 8 is a good conservative number.
Some inspectors would have objections to using 5 in the calculation.

Each neutral will go to the lighting loads. I agree 8 would be the number but what code section address this?
 

GoldDigger

Moderator
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Location
Placerville, CA, USA
Occupation
Retired PV System Designer
Each neutral will go to the lighting loads. I agree 8 would be the number but what code section address this?
I do not think that there is a specific section discussing travelers, although there may be something in the Handbook, but it all comes down to the definition of Current Carrying Conductors, with one example in the explicit rules for MWBC.
If two conductors cannot (because of a mechanical lockout, the SPDT and DPDT switches) both carry current at the same time, they are not both CCCs.
It is even stronger for MWBCs in that the "neutral" is not counted since the total maximum current trough the whole set of wires cannot be more than the maximum total current for the case where the neutral is not carrying current. Even though in some cases the neutral will carry current from unbalanced phase loads.
 

crtemp

Senior Member
Location
Wa state
Only one of the two travelers can be carrying current at one time. And if your third conductor in each switch leg is just a neutral to satisfy the requirement that the neutral be present in a switch box, rather than the neutral for the actual lighting load, it would not be current carrying either, at least not until someone modified the wiring and connected a larger load than a presence sensor to the box. But 8 is a good conservative number.
Some inspectors would have objections to using 5 in the calculation.


Where does it say there must be a neutral in a switch box?
 

jxofaltrds

Inspector Mike®
Location
Mike P. Columbus Ohio
Occupation
ESI, PI, RBO
Too tired to search. I have 3 - 14/3's and 1-14/2 in a bored hole that will be fire caulked. These 3 are travelers for 3-3way switches and a home run to a recpt.. So do I have 8 ccc or 11 ccc ? Cant remember if all of the conductors in the travelers have to be counted or just 2. Just need to know if I need to drill another hole

That is not bundling.

Where does it say there must be a neutral in a switch box?

Nothing about a neutral but:

404.2
(C) Switches Controlling Lighting Loads. Where switches
control lighting loads supplied by a grounded general purpose
branch circuit, the grounded circuit conductor for the controlled
lighting circuit shall be provided at the switch location.
 

crtemp

Senior Member
Location
Wa state
That is not bundling.



Nothing about a neutral but:

404.2
(C) Switches Controlling Lighting Loads. Where switches
control lighting loads supplied by a grounded general purpose
branch circuit, the grounded circuit conductor for the controlled
lighting circuit shall be provided at the switch location.


I must not understand. I install switch loops all the time without any issues.
 

qcroanoke

Sometimes I don't know if I'm the boxer or the bag
Location
Roanoke, VA.
Occupation
Sorta retired........
Too tired to search. I have 3 - 14/3's and 1-14/2 in a bored hole that will be fire caulked. These 3 are travelers for 3-3way switches and a home run to a recpt.. So do I have 8 ccc or 11 ccc ? Cant remember if all of the conductors in the travelers have to be counted or just 2. Just need to know if I need to drill another hole

I seem to remember being quoted chapter and verse that supported not counting it not to long ago but a search did not turn it up.
But other searches seemed to indicate it needs to be counted but they were old threads.
In other words flip a coin or wait and see what others say.
 

fmtjfw

Senior Member
I seem to remember being quoted chapter and verse that supported not counting it not to long ago but a search did not turn it up.
But other searches seemed to indicate it needs to be counted but they were old threads.
In other words flip a coin or wait and see what others say.
2014 is supposed to clear up that you only count one of each pair of travelers as a CCC. I put in the request. Somebody changed the text into complete word salad.

Table 310.15(B)(3)(a) Adjustment Factors for More Than
Three Current-Carrying Conductors in a Raceway or Cable

... text following table
Number of conductors is the total number of conductors in the raceway
or cable, including spare conductors. The count shall be adjusted
in accordance with 310.15(B)(5) and (6), and shall not include conductors
that are connected to electrical components but that cannot be
simultaneously energized. [ROP 6?40]


so that now it reads that you must count spare conductors.
 

ceb58

Senior Member
Location
Raeford, NC
Thanks guys, passed inspection with flying colors. I know the inspector and he knows my work. He just looked around a little and signed off on it. Besides he was too busy tearing the GC up over the new energy codes :p
 

don_resqcapt19

Moderator
Staff member
Location
Illinois
Occupation
retired electrician
2014 is supposed to clear up that you only count one of each pair of travelers as a CCC. I put in the request. Somebody changed the text into complete word salad.

Table 310.15(B)(3)(a) Adjustment Factors for More Than
Three Current-Carrying Conductors in a Raceway or Cable

... text following table
Number of conductors is the total number of conductors in the raceway
or cable, including spare conductors. The count shall be adjusted
in accordance with 310.15(B)(5) and (6), and shall not include conductors
that are connected to electrical components but that cannot be
simultaneously energized. [ROP 6?40]


so that now it reads that you must count spare conductors.

If you read the ROP, you will see that the rule originally required you to count all conductors in the raceway for the purposes of derating. The change was made without any proposal or approval. This change puts it back to the way it was supposed to be, with the provision that conductors that cannot be simultaneously energized are not required to be counted. The substantiation said it was always the intent that spares be counted.
 

don_resqcapt19

Moderator
Staff member
Location
Illinois
Occupation
retired electrician
How would it work if you didn't count the spares?...if the use of the spares caused additional derating you would have to change the OCPD for the conductors that were in use at the time of the original installation, or pull the original conductors out and pull larger ones in. Or are you saying, even when you put the spares to use, you don't have to count them for derating purposes?
 

GoldDigger

Moderator
Staff member
Location
Placerville, CA, USA
Occupation
Retired PV System Designer
How would it work if you didn't count the spares?...if the use of the spares caused additional derating you would have to change the OCPD for the conductors that were in use at the time of the original installation, or pull the original conductors out and pull larger ones in. Or are you saying, even when you put the spares to use, you don't have to count them for derating purposes?

Only if you use a spare to replace a damaged wire rather than to add an additional circuit. :)
 

hurk27

Senior Member
That is not bundling.

Mike you still have to derate if the hole is fire caulked as the OP indicated

Second paragraph of 334.80:
334.80 Where more than two NM cables containing two or
more current-carrying conductors are installed, without
maintaining spacing between the cables, through the same
opening in wood framing that is to be fire- or draft-stopped
using thermal insulation, caulk, or sealing foam, the allowable
ampacity of each conductor shall be adjusted in accordance
with Table 310.15(B)(2)(a) and the provisions of
310.15(A)(2), Exception, shall not apply.
 
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