Nec 310.3 C Conductors in a raceway 8AWG +

Jpflex

Jpflex

Electrician big leagues
Location
Victorville
Occupation
Electrician commercial and residential
According to 310.3 C,

conductors 8 AWG or larger that are in a raceway, must be stranded


According to 250.64 B 2
A 6 Awg or larger grounding electrode conductor exposed to physical damage musy be protected in (conduit) RMC, IMC, SCH 80 PVC...etc

Likewise, 250.64 B 3
All grounding electrode conductors smaller than 6 AWG must be inztalled in (conduit), RMC, IMC, SCH 80 PBC, etc

However, rarely do i see grounding electrode conductors that are both 8 AWG or larger and installed in raceway to be stranded, yet they pass inspection.

Is this a code that is standard to be overlooked?
 
Jpflex said:
According to 310.3 C,

conductors 8 AWG or larger that are in a raceway, must be stranded


According to 250.64 B 2
A 6 Awg or larger grounding electrode conductor exposed to physical damage musy be protected in (conduit) RMC, IMC, SCH 80 PVC...etc

Likewise, 250.64 B 3
All grounding electrode conductors smaller than 6 AWG must be inztalled in (conduit), RMC, IMC, SCH 80 PBC, etc

However, rarely do i see grounding electrode conductors that are both 8 AWG or larger and installed in raceway to be stranded, yet they pass inspection.

Is this a code that is standard to be overlooked?
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The conduit for the GEC is just a sleeve and not a complete raceway. You are not pulling major lengths of large, solid, bare conductors through bends, just sleeving it for protection. Then it's usually just a straight piece from the ground up to the landing point.
 
Jpflex said:
According to 310.3 C,

conductors 8 AWG or larger that are in a raceway, must be stranded
Click to expand...
Actually, it says: "Where installed in raceways, conductors 8 AWG and larger shall be stranded, unless specifically permitted or required elsewhere in this Code to be solid."

And 250.62 on GECs says "Conductors of the wire type shall be solid or stranded, insulated, covered, or bare." This may be taken to mean for compliance with 310.3(C), GECs are "specifically permitted" to be solid.

Cheers, Wayne
 
If there is a short section of raceway being used as a sleeve the #8 and larger solid GEC is permitted. If there is a complete section of raceway like in commercial building then the GEC is required to be stranded.

If I remember correctly a pool light does allow a #8 solid to be installed in a raceway.
 
Does a GEC need to comply with rules of 310?

A majority of what is in 310 is primarily about conductor insulation more so than the conductor itself. A GEC doesn't even need insulation but isn't prohibited from having insulation either. Sizing of GEC's is does not factor in temperature or any other things that can impact insulation integrity.
 
Little Bill said:
The conduit for the GEC is just a sleeve and not a complete raceway. You are not pulling major lengths of large, solid, bare conductors through bends, just sleeving it for protection. Then it's usually just a straight piece from the ground up to the landing point.
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I know there are exemptions for sectional metal bend conduits under ground to not have to be bonded or small sections of conduit used for wire protection to not have to be continuous to a box etc

However, I see no exemption in NEC within this section to allow a short metal conduit/sleeve used to protect a grounding electrode conductor 6 AWG or larger to first not be parallel bonded to the GEC and second for the GEC to be other than stranded
 
Jpflex said:
I know there are exemptions for sectional metal bend conduits under ground to not have to be bonded or small sections of conduit used for wire protection to not have to be continuous to a box etc

However, I see no exemption in NEC within this section to allow a short metal conduit/sleeve used to protect a grounding electrode conductor 6 AWG or larger to first not be parallel bonded to the GEC and second for the GEC to be other than stranded
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The "parallel bonded" only applies when the sleeve/raceway is ferrous metal as ferrous can make a much more effective choke out of that sleeve/raceway than non ferrous. Aluminum, brass, stainless though maybe not too common in such applications, would not need that extra bonding that ferrous raceways would require.
 
wwhitney said:
Actually, it says: "Where installed in raceways, conductors 8 AWG and larger shall be stranded, unless specifically permitted or required elsewhere in this Code to be solid."

And 250.62 on GECs says "Conductors of the wire type shall be solid or stranded, insulated, covered, or bare." This may be taken to mean for compliance with 310.3(C), GECs are "specifically permitted" to be solid.

Cheers, Wayne
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Yes i looked at the code you referenced 250.62 which permits GEC to be solid or stranded.. etc

However, based on 310.3C, once a GEC is installed in a conduit (regarless of it being a small conduit section) it can no longer be solid wire, if it is 8 AWG or larger
 
kwired said:
The "parallel bonded" only applies when the sleeve/raceway is ferrous metal as ferrous can make a much more effective choke out of that sleeve/raceway than non ferrous. Aluminum, brass, stainless though maybe not too common in such applications, would not need that extra bonding that ferrous raceways would require.
Click to expand...
Indeed. I mentioned metal raceways for the parallel bonding portion
 
Jpflex said:
I know there are exemptions for sectional metal bend conduits under ground to not have to be bonded or small sections of conduit used for wire protection to not have to be continuous to a box etc

However, I see no exemption in NEC within this section to allow a short metal conduit/sleeve used to protect a grounding electrode conductor 6 AWG or larger to first not be parallel bonded to the GEC and second for the GEC to be other than stranded
Click to expand...
No one said it didn't need bonding, only that solid can be in a conduit for a GEC.
 
Jpflex said:
However, based on 310.3C, once a GEC is installed in a conduit (regarless of it being a small conduit section) it can no longer be solid wire, if it is 8 AWG or larger
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That is incorrect. A short section of raceway used as a sleeve would not be restricted to only stranded conductors since it is not a complete conduit or tubing system.

Chapter 9
Notes to Tables
(2) Table 1 applies only to complete conduit or tubing systems and is not intended to apply to sections of conduit or tubing used to protect exposed wiring and cable from physical damage.
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Jpflex said:
Indeed. I mentioned metal raceways for the parallel bonding portion
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Is not all metal though, just ferrous metals needs the additional bonding. Non ferrous makes a very poor "core and coil" when compared to ferrous metals. There's a reason they wind motor and transformer windings around steel cores and not aluminum cores
 
I always thought of it like this. #6 need to be protected if subject to physical damage. To me it is like romex. You can cross joist bays with it and if stapled up it is ok. Use a sleeve if needed to run down to a water pipe or staple it to a running board. #8 needs conduit or armor for the entire length.

If I have any doubt I will run #4.

They used to sell #8 with cable armor on it is that still available??
 
kwired said:
Is not all metal though, just ferrous metals needs the additional bonding. Non ferrous makes a very poor "core and coil" when compared to ferrous metals. There's a reason they wind motor and transformer windings around steel cores and not aluminum cores
Click to expand...
Aren't the rotors in electro-mechanical watt-hour meters made of aluminum?
 
Eddie702 said:
#8 needs conduit or armor for the entire length.


They used to sell #8 with cable armor on it is that still available??
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If 8 AWG requires armor for its entire length, in your case it would also have to be stranded conductor as the code is currently worded

I believe we had 8 awg with cable armor at my last job
 
Jpflex said:
If 8 AWG requires armor for its entire length, in your case it would also have to be stranded conductor as the code is currently worded

I believe we had 8 awg with cable armor at my last job
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Cable armor is a solid conductor factory installed within the armor. It is not a raceway therefore it is not required to be stranded.
 
Yes
infinity said:
That is incorrect. A short section of raceway used as a sleeve would not be restricted to only stranded conductors since it is not a complete conduit or tubing system.
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I am familiar with this table but this table is for max conductor fill per conduit diameter / size. The relevance here, is if i recall is to allow up to 60% fill if conduit does not exceed 24" inches. This is different than stranded vs solid conductor requirements.

There may also be a similar exemption for conductors not having take a full ampacity adjustment for bundling if with a conduit (if i remember 12 inches or 24 inches or less? But i cannot recall exactly)

However neither of these exemptions for small sections of conduit apply to the 8 AWG or larger wire in conduit rule, specicically to whether it must be solid or stranded
 
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