Article 250.122 sizing EGC.

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reyamkram

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Hanover park, il
The table for 250-122, EGC, for 15 amps it is #14 for the EGC and for 20 amps it is #12 for EGC, what about when you have 20 amps and 30 amps in the same race way ??, because the next size breaker in the table is 60 amps, so do I use #12 EGC for sizes 30-35-40-45 and 50 amp breakers, will all use A
#12, EGC,??
Any information is greatly appreciate, Thank you.
 
reyamkram said:
The table for 250-122, EGC, for 15 amps it is #14 for the EGC and for 20 amps it is #12 for EGC, what about when you have 20 amps and 30 amps in the same race way ??, because the next size breaker in the table is 60 amps, so do I use #12 EGC for sizes 30-35-40-45 and 50 amp breakers, will all use A
#12, EGC,??
Any information is greatly appreciate, Thank you.
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No, but they can all use and share a single #10.
 
I'm not 100% sure what is meant by the question(s) since the statements about the sizes aren't right to begin with. Just in case in the question was being asked for something like multiple circuits of different sizes that may tee off to different locations/destinations:

If you have a 20A and 30A circuit in the same raceway and you don't want to share an EGC for whatever reason, the 20A circuit can have #12 cu EGC and the 30A circuit can have #10 cu EGC. The 20A circuit doesn't have to have its EGC increased to #10 if that's what you were asking. Just keep in mind the requirements to bond the EGCs at the requirement locations.


If you're wanting to share EGC for both of these circuits: then it is of course as Larry stated. See 250.122(C)



Side note with this being my first post: Love the forum. I've been consuming knowledge from you all for many years now. Thank you. Looking forward to actually contributing.
 
bwat said:
I'm not 100% sure what is meant by the question(s) since the statements about the sizes aren't right to begin with. Just in case in the question was being asked for something like multiple circuits of different sizes that may tee off to different locations/destinations:

If you have a 20A and 30A circuit in the same raceway and you don't want to share an EGC for whatever reason, the 20A circuit can have #12 cu EGC and the 30A circuit can have #10 cu EGC. The 20A circuit doesn't have to have its EGC increased to #10 if that's what you were asking. Just keep in mind the requirements to bond the EGCs at the requirement locations.


If you're wanting to share EGC for both of these circuits: then it is of course as Larry stated. See 250.122(C)



Side note with this being my first post: Love the forum. I've been consuming knowledge from you all for many years now. Thank you. Looking forward to actually contributing.
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But you are still required to connect all those EGC's together at every junction box making it pointless in many ways to run separate EGC for each circuit. If you have a conduit body or pull box with no splices within you don't have to splice the EGC's and that would be one place where it may be beneficial to pull separate EGC's in some cases.
 
kwired said:
But you are still required to connect all those EGC's together at every junction box making it pointless in many ways to run separate EGC for each circuit. If you have a conduit body or pull box with no splices within you don't have to splice the EGC's and that would be one place where it may be beneficial to pull separate EGC's in some cases.
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100% agree and I (perhaps poorly?) tried to convey that. From a design perspective, which I was wanting to avoid by keeping it at what is permitted by code, I agree it often wouldn't make sense to run separate EGCs. This is why I said "if you don't want to share an EGC for whatever reason"... and the note about requirements for bonding. I was just pointing out that it is permissible by NEC.
 
texie said:
Higher than 20 but 60 or less the size is #10 CU. Maybe I'm not getting your question.
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Thank you. Yes, Because the table 250.122, has 15 amps and 20 amps, then it jumps to 60 amps, so I use A #10 EGC for the amps between 20 and 60.
I have a Hoffman box 12"X 12" 6" deep, and there is 2-20 amp 1 phase duplex receptacles on one 20 amp breaker, and 3-3 phase 30 amp single receptacles on to 30 amp breakers, and they are all connected to a #12 ECG, so, it should be Connected to A #10 EGC, Also the box has hinged cover,
and there are splices in the box, should the box and cover be bonded to the box and EGC.???

Thank you,
 
reyamkram said:
Thank you. Yes, Because the table 250.122, has 15 amps and 20 amps, then it jumps to 60 amps, so I use A #10 EGC for the amps between 20 and 60.
I have a Hoffman box 12"X 12" 6" deep, and there is 2-20 amp 1 phase duplex receptacles on one 20 amp breaker, and 3-3 phase 30 amp single receptacles on to 30 amp breakers, and they are all connected to a #12 ECG, so, it should be Connected to A #10 EGC, Also the box has hinged cover,
and there are splices in the box, should the box and cover be bonded to the box and EGC.???

Thank you,
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You got it now. The minimum size EGC for these circuits in 1 raceway is #10.
Not sure how you mounted the receps in the box-are they in there own boxes with in the enclosure or do you have a custom mounting plate?
 
texie said:
You got it now. The minimum size EGC for these circuits in 1 raceway is #10.
Not sure how you mounted the receps in the box-are they in there own boxes with in the enclosure or do you have a custom mounting plate?
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The receptacles are mounted to the cover, the cover has holes cut out one for the 2, 20 amp 1 phase, duplex receptacles with a steel cover plate, and 3 holes for the 3, 30 amp 3 phase outlets, on a plastic flange each has it own plastic flange, should, all that be bound to the box cover and ground??

Thank you, for the information.
 
reyamkram said:
The receptacles are mounted to the cover, the cover has holes cut out one for the 2, 20 amp 1 phase, duplex receptacles with a steel cover plate, and 3 holes for the 3, 30 amp 3 phase outlets, on a plastic flange each has it own plastic flange, should, all that be bound to the box cover and ground??

Thank you, for the information.
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Yes. The goal of the NEC is to be sure there is always a compliant fault return path so no metallic objects can ever be left floating and become a shock hazard.
 
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