Why are multiple egc's allowed together?

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Cletis

Senior Member
Location
OH
Why are you allowed to put multiple egc's together in one hole that is clearly identified for 1 conductor on typical ground bars ?
 

petersonra

Senior Member
Location
Northern illinois
Occupation
engineer
Why are you allowed to put multiple egc's together in one hole that is clearly identified for 1 conductor on typical ground bars ?

you aren't.

HOWEVER, most neutral bars are listed for two wires per connection, but code requires each neutral on the neutral bar to be by itself. So you can have 2 ground wires on a spot on a neutral bar, but only a single neutral wire (presuming it is the service equipment and thus you can connect EGCs to the neutral bar).
 

Cletis

Senior Member
Location
OH
ok. I meant neutral bus bar or ground bar really. But, obviously their ports are round and appear UL listed for 1 conductor. Is there an exception somewhere that states if it doesn't normally carry current you can put in as many as fits ? It's done here all the time and it always passes
 

petersonra

Senior Member
Location
Northern illinois
Occupation
engineer
ok. I meant neutral bus bar or ground bar really. But, obviously their ports are round and appear UL listed for 1 conductor. Is there an exception somewhere that states if it doesn't normally carry current you can put in as many as fits ? It's done here all the time and it always passes
there is no such exception.
 

electricalist

Senior Member
Location
dallas tx
I have no clue.again.:cool:
Unless im forced to I dont put 2 under any terminal. Nothing feels more wrong than disrupting something that landed with what im working on..
Imo neutral and grounds should have a assigned terminal in a panel..
 

kwired

Electron manager
Location
NE Nebraska
Instructions on the panel cover/cabinet label often state you can land two conductors in these terminals - in the absence of those instructions they likely are only rated for a single conductor. Usually if multiple conductors are present they must be same size. However NEC still only wants one grounded (neutral) conductor per hole other then conductors that are permitted to be paralleled can land in same hole if designed for multiple conductors.

I think I have seen some that even allow three conductors of the same size - 12 or 14 AWG, I believe it was for Cutler Hammer bus on some older CH series panels, not sure if they still have that rating on what is currently being used.
 

edlee

Senior Member
It was explained to me (by Fred Hartwell!) that neutral wires, being current-carrying conductors, will warm up under use and if they warm unevenly due to differing loads, then when sharing a slot the connection may loosen over time because of uneven expansion and contraction of the copper.

Equipment grounding conductors, which are not current-carrying, will not have the same effect. So if the panel allows, grounds can be grouped , or paired, in one hole.
 

kwired

Electron manager
Location
NE Nebraska
It was explained to me (by Fred Hartwell!) that neutral wires, being current-carrying conductors, will warm up under use and if they warm unevenly due to differing loads, then when sharing a slot the connection may loosen over time because of uneven expansion and contraction of the copper.

Equipment grounding conductors, which are not current-carrying, will not have the same effect. So if the panel allows, grounds can be grouped , or paired, in one hole.
Which probably has more to do with NEC not allowing more then one conductor per hole for the grounded conductor then whether or not the hole is listed for more then one conductor.
 

don_resqcapt19

Moderator
Staff member
Location
Illinois
Occupation
retired electrician
ok. I meant neutral bus bar or ground bar really. But, obviously their ports are round and appear UL listed for 1 conductor. Is there an exception somewhere that states if it doesn't normally carry current you can put in as many as fits ? It's done here all the time and it always passes
Read the instructions for the panel. In most cases the bar is listed for 2 or 3 EGCs per hole and one grounded conductor.
 

Cletis

Senior Member
Location
OH
Read the instructions for the panel. In most cases the bar is listed for 2 or 3 EGCs per hole and one grounded conductor.

Thanks for all the info folks, but, i'll probably just keep cramming 3-6 egc's (I wrap them along the way as well) per hole as always since all the inspectors in a 5 county area don't really care I guess and not sure if I can ever read instructions for a panel. I'm allergic to instructions.

Carry on
 
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