2 wires on ground or nuetral termination in panels

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Hi,
House inspector is requiring me to redo neutral and ground terminations in service panel because 2 wires are terminated under some lugs. I have always been allowed to do this in the past, this is a new one on me.
 

pete m.

Senior Member
Location
Ohio
grounded conductors are required to have their own terminal.... 408.41

Equipment grounding conductors might be allowed to be doubled under one terminal but that is dependent upon the manufacturers installation instructions.


Pete
 

raider1

Senior Member
Staff member
Location
Logan, Utah
The panelboard installation and listing instructions prohibited installing more than 1 grounded conductor under a single lug for quite some time before 408.41 was added to the NEC.

Chris
 

squaredan

Senior Member
Location
Pennsylvania
Hi Stefanoworx Welcome to the forum.. you can also read 110.14(A) pretty much says the same as 408.41.. If your panel is Listed for two wires under terminal, then you should be OK..But I never seen a ground terminal identified for such..If any body knows of such please let meknow..

Dan
 
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infinity

Moderator
Staff member
Location
New Jersey
Occupation
Journeyman Electrician
The wording for only one neutral (grounded conductor) under a single screw terminal was added to the 2002 NEC. Prior to that it still had been part of the listing of the panelboard neutral bar but no one really checked.
 

donf

Member
Pigtailed Neutrals

Pigtailed Neutrals

I came across a heavily populated main service panel that had at least 6 pigtailed sets of neutral wires.

Three neutral conductors were brought into a pigtail and then a forth conductor was attached to the bus bar.

One wire under the screw, connecting three other neutrals to the busbar.

I walked away rather than create yet another pigtail so I could add another two BCs.

I was told that an inspector approved the configuration but in 30 or so years of being around electricity I was not persuaded to bend around the rules.

I offered to put in another busbar, but they only wanted the pigtails.

Was I wrong? While I never seen anything in code forbidding this, I have also never seen this as an acceptable/permissible method for connecting neutral wires.
 
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infinity

Moderator
Staff member
Location
New Jersey
Occupation
Journeyman Electrician
I came across a heavily populated main service panel that had at least 6 pigtailed sets of neutral wires.

Three neutral conductors were brought into a pigtail and then a forth conductor was attached to the bus bar.

One wire under the screw, connecting three other neutrals to the busbar.

I walked away rather than create yet another pigtail so I could add another two BCs.

I was told that an inspector approved the configuration but in 30 or so years of being around electricity I was not persuaded to bend around the rules.

I offered to put in another busbar, but they only wanted the pigtails.

Was I wrong? While I never seen anything in code forbidding this, I have also never seen this as an acceptable/permissible method for connecting neutral wires.

I don't see how three neutrals pigtailed into one is code compliant.
 

Dennis Alwon

Moderator
Staff member
Location
Chapel Hill, NC
Occupation
Retired Electrical Contractor
The pig tail would make the circuit a multiwire branch cir and would technically need a DP breaker or sp with handle ties.
 

jaggedben

Senior Member
Location
Northern California
Occupation
Solar and Energy Storage Installer
But for three circuits pigtailed together that would need to be a three phase panel, no?

As a newb to studying the Code I have been trying to make sure I've been understanding this correctly.

Is it the case that three more more ungrounded conductors sharing a neutral in a split-phase, 3 wire system would not fit the definition of a multi-wire branch circuit, because at least two of those ungrounded conductors would have no 'voltage between them' as stated in the definition in Art. 100?

I don't see how three neutrals pigtailed into one is code compliant

Is there a specific place in the Code where this configuration is prohibited?
 

raider1

Senior Member
Staff member
Location
Logan, Utah
As a newb to studying the Code I have been trying to make sure I've been understanding this correctly.

Is it the case that three more more ungrounded conductors sharing a neutral in a split-phase, 3 wire system would not fit the definition of a multi-wire branch circuit, because at least two of those ungrounded conductors would have no 'voltage between them' as stated in the definition in Art. 100?

Correct, with a single phase 3 wire system if you connect 3 ungrounded conductor to 1 grounded conductor it would not be a multiwire branch circuit due to the definition of multiwire branch circuit.



Is there a specific place in the Code where this configuration is prohibited?

There is in the 2011 NEC. 200.4 prohibits a neutral conductor from being used for more than one circuit or multiwire branch circuit.

Chris
 

infinity

Moderator
Staff member
Location
New Jersey
Occupation
Journeyman Electrician
I thought the 2011 prohibited a neutral shared between ungrounded conductors of the same phase, I have not heard anything that would prohibit a multi-wire circuit?


Yes, that's correct but Chris said that "There is in the 2011 NEC. 200.4 prohibits a neutral conductor from being used for more than one circuit or multiwire branch circuit." Meaning that it cannot be used for than one circuit or it cannot be used for more than a MWBC.
 
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