Number of NM cables through hole

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ceb58

ceb58

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Raeford, NC
jusme123 said:
just to get started, 240.4 is one
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That has nothing to do with what defines a CCC. 240.4 is stating conductors are to be protected by the correct OC device. IE: #8Cu not more than 50 amp. unless it falls into 240.4 (G). The same also applies to a 3 phase MWBC you do not count the neutral as a CCC. 310.15 (B)(4)
 
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jusme123

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ceb58 said:
That has nothing to do with what defines a CCC. 240.4 is stating conductors are to be protected by the correct OC device. IE: #8Cu not more than 50 amp. unless it falls into 240.4 (G). The same also applies to a 3 phase MWBC you do not count the neutral as a CCC. 310.15 (B)(4)
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.....if they are not current carrying conductors, why are they protected by a breaker? Other parts of the code explicitly exempt others ckt conductors (as the neutral in your example) from being counted as CCC, travelers of a 3 way ckt are not listed as exemptions, but are STILL CCC because they have to be protected by an OCPD.
 
ceb58

ceb58

Senior Member
Location
Raeford, NC
jusme123 said:
.....if they are not current carrying conductors, why are they protected by a breaker? Other parts of the code explicitly exempt others ckt conductors (as the neutral in your example) from being counted as CCC, travelers of a 3 way ckt are not listed as exemptions, but are STILL CCC because they have to be protected by an OCPD.
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You can troll the thread all you want, you can count all of the travelers in a cable as CCC if you want. But the fact remains you will not measure current on one or the other of the travelers. The conductor that is not carrying any current is no longer protected by over-current protection.
 
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jusme123

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...than heating and air conditioning can be run in the same conduit without derating (3 phase, 220v)?

and by the way, I'm not trolling :happyno:
 
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Gac66610

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Location
Kansas
jusme123 said:
...than heating and air conditioning can be run in the same conduit without derating (3 phase, 220v)?

and by the way, I'm not trolling :happyno:
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Generally when running 240v Electric heat the outdoor unit is not an A/C unit, more likely to be a Heat Pump, in which it would be conceivable that they both run at the same time, so derating would still apply
 
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jusme123

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ceb58 said:
You can troll the thread all you want, you can count all of the travelers in a cable as CCC if you want. But the fact remains you will not measure current on one or the other of the travelers. The conductor that is not carrying any current is no longer protected by over-current protection.
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that conductor IS REQUIRED to be covered by OCP whether it is used or not.
 
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jusme123

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Gac66610 said:
Generally when running 240v Electric heat the outdoor unit is not an A/C unit, more likely to be a Heat Pump, in which it would be conceivable that they both run at the same time, so derating would still apply
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I guess the load calculation for the service would also reflect your statement?
 
don_resqcapt19

don_resqcapt19

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Illinois
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retired electrician
jusme123 said:
take a look at 220.60 '08
noncoincident loads
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I don't understand. That section supports the idea that you would only count one set of conductors as current carrying when there are two sets of noncoincident conductors in the raceway.
 
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