Small conductors

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weressl said:
...and I stand by there with you.

...It seems to me that the prevelant argument is that the NEC does not allow reduction of EGC. It seems that Okonite and all the other cable manufacturers are marketing cables that do not meet that requirement as they start reducing the EGC sizes at larger sizes.

Any comments?
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I don't understand.

Table 250.122 allows considerably smaller EGC than circuit conductors.:-?
 
realolman said:
I don't understand.

Table 250.122 allows considerably smaller EGC than circuit conductors.:-?
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Sure does. :)

But 250.122(B) requires that when the circuit conductors are increased in size the EGC must be increased in size proportionally.

With 15, 20 and 30 amp circuits the size ratio between the circuit conductors and the EGC is 1:1.

That being the case when I run 6 AWG circuit conductors for a 20 amp site lighting circuit I must also increase the EGC to 6 AWG to maintain the 1:1 ratio.

Strangely if I removed the 20 amp breaker and replaced it with a 60 I could reduce the EGC down to 10 AWG.
 
I understand that the EGC is inrcreased if the conductors are increased for voltage drop... I think that's an even better reason to ditch the egc if you don't need it.

That's a cool observation regarding the 60a breaker.:)


what I don't understand are the comments about the okonite cable.:-?
 
Laszlo,
The thread is about "small conductors". For conductors protected by OCPDs rated 30 amps or less the circuit conductors and the EGC must be the same size. This applies no matter what size conductor is being used with the OCPD.
 
don_resqcapt19 said:
Laszlo,
The thread is about "small conductors". For conductors protected by OCPDs rated 30 amps or less the circuit conductors and the EGC must be the same size. This applies no matter what size conductor is being used with the OCPD.
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Yeah, and I keep looking for the definition of 'small conductor' in the NEC and there don't seem to be one.....:D

The title of the thread went right over my head......:-?
 
Laszlo,
When I hear the term "small conductors" and we are talking about the code I think of 240.4(D) which covers, 14, 12 and 10.
 
If a EC installed a 6/3 w ground for a 50 amp range receptacle and used a 40 amp breaker this would also be a violation as the # 10 ground was not increased in size also?? NEC 2008 Art 250.122 B
 
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