Separate Ground

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Alwayslearningelec

Senior Member
Location
NJ
Occupation
Estimator
When you guys see this in the spec I assume you always install accordingly. Do you every try and get around it by asking for exception etc.? Thanks.
 

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texie

Senior Member
Location
Fort Collins, Colorado
Occupation
Electrician, Contractor, Inspector
That's what they all want now days. I have sort of a beef with that language though. I think a more correct way to word this would be "do not use raceway as sole grounding method". Just a quibble but I get their point.
 

infinity

Moderator
Staff member
Location
New Jersey
Occupation
Journeyman Electrician
On side note. How does pulling ONE EGC in one conduit with multiple circuits take care of the grounding of all the circuits?

One is all that is required by the NEC when sized according to the largest circuit OCPD protecting the branch circuits in that raceway. If you had all 20 amp circuits then a single EGC sized according to 250.122 is all that you need. Pulling a separate EGC for each branch circuit is an incredible waste of money
 

LarryFine

Master Electrician Electric Contractor Richmond VA
Location
Henrico County, VA
Occupation
Electrical Contractor
On side note. How does pulling ONE EGC in one conduit with multiple circuits take care of the grounding of all the circuits?

You just join them together everywhere. There's no reason for more than one EGC along any circuit pathway.

A single conductor sized for the largest circuit involved may be used as the EGC for all of them.
 

Dennis Alwon

Moderator
Staff member
Location
Chapel Hill, NC
Occupation
Retired Electrical Contractor
250.122(C)

(C) Multiple Circuits. Where a single equipment grounding
conductor is run with multiple circuits in the same raceway,
cable, or cable tray, it shall be sized for the largest overcurrent
device protecting conductors in the raceway, cable, or cable
tray. Equipment grounding conductors installed in cable trays
shall meet the minimum requirements of 392.10(B)(1)(c).
 

petersonra

Senior Member
Location
Northern illinois
Occupation
engineer
personally, i would tell them how much extra it will cost to run a dedicated egc for each circuit. then I would tell them how much they can save by running just one egc per conduit. then how much they can save by using the raceway as the egc.

personally, if they want to pay for unnecessary stuff I would be inclined to let them, but I would still mention the potential cost savings.
 

Dennis Alwon

Moderator
Staff member
Location
Chapel Hill, NC
Occupation
Retired Electrical Contractor
My suspicion is that the intent is to have an equipment grounding conductor in the conduit not multiple equipment grounding conductor's. I would verify this with the engineer.
 

texie

Senior Member
Location
Fort Collins, Colorado
Occupation
Electrician, Contractor, Inspector
My suspicion is that the intent is to have an equipment grounding conductor in the conduit not multiple equipment grounding conductor's. I would verify this with the engineer.

OK, I'm a little slow. I missed the "for each circuit" part. But I'm sure you are right that they meant 1 EGC in the raceway. Just more poor wording in the spec.
 

cdslotz

Senior Member
I hate this kind of wording in a spec or note on drawings. Always RFI it because it almost always contradicts the drawings which usually shows an arrow with tick marks indicating circuits , neutral, and usually shows ONE ground in the home run
 

kwired

Electron manager
Location
NE Nebraska
My money is on exactly what is written, a separate EGC for each circuit.

But is pointless as NEC will require you tie them all together in every box (other than pull boxes with no splicing),as well as bonding to the box if metallic, effectively making them one conductor anyway, true isolated grounding conductors being the exception to this rule.
 

infinity

Moderator
Staff member
Location
New Jersey
Occupation
Journeyman Electrician
But is pointless as NEC will require you tie them all together in every box (other than pull boxes with no splicing),as well as bonding to the box if metallic, effectively making them one conductor anyway, true isolated grounding conductors being the exception to this rule.

Regardless of all of that it says "provided dedicated equipment grounding for each circuit" which is exactly how I would estimate and install it. If that's what they're paying for then why argue unless of course you want to try and save the client some money.
 

kwired

Electron manager
Location
NE Nebraska
Regardless of all of that it says "provided dedicated equipment grounding for each circuit" which is exactly how I would estimate and install it. If that's what they're paying for then why argue unless of course you want to try and save the client some money.
Might depend on the client and what current relationship I may have with them. Regular client that would happen get a spec like that - very well may question the designer. Most my regular clients I am the designer though, but there are engineered projects sprinkled in here and there.
 

LarryFine

Master Electrician Electric Contractor Richmond VA
Location
Henrico County, VA
Occupation
Electrical Contractor
But is pointless as NEC will require you tie them all together in every box (other than pull boxes with no splicing),as well as bonding to the box if metallic, effectively making them one conductor anyway,
Triggering the rules against paralleling small conductors, making the spec non-code-compliant.
 

infinity

Moderator
Staff member
Location
New Jersey
Occupation
Journeyman Electrician
Triggering the rules against paralleling small conductors, making the spec non-code-compliant.

Paralleling rules do not apply to EGC's. :)

310.10(H) Conductors in Parallel.
(1) General. Aluminum, copper-clad aluminum, or copper
conductors, for each phase, polarity, neutral, or grounded
circuit shall be permitted to be connected in parallel (electri‐
cally joined at both ends) only in sizes 1/0 AWG and larger
where installed in accordance with 310.10(H)(2) through
(H)(6).
 
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