Landing the Neutral Conductor.

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WadeFitz

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salt lake city
I have not been able to get a clear answer on when a neutral conductor should be landed, or it should just pass through a box or sub panel. Is neutral only to be landed on the neutral bus in the main service panel, where it is to be bonded to ground?
 

jeremy.zinkofsky

Senior Member
Location
nj
A neutral conductor is landed where it is needed to serve as THE grounded conductor for an AC system (usually at the main service panel). The NEC has specific rules as to where you can and cannot "land" (which I think the better term would be "bond") the neutral in electrical equipment but does not specify that you need to land it in every junction box it passes through. In fact, the neutral is not always needed i.e. switches or some 3-phase motors.

Don't confuse the neutral (grounded) conductor with the ground (grounding) conductor. The ground has to be connected in such a way that there is a continous path to ground. Basically, "landed" on everything metal (which is a generalization, so don't jump on me folks).
 

Dennis Alwon

Moderator
Staff member
Location
Chapel Hill, NC
Occupation
Retired Electrical Contractor
I have just spliced the neutral through a 30 amp disconnect. If there is a panel with other circuits then the neutral should be landed on the neutral bar. Depending on the situation determines whether or not the neutral should be isolated from the equipment grounding conductor. For instance in old installs to a detached structure there was often no equipment grounding conductor and the neutral acted as both a neutral and an equipment grounding conductor. In that case the neutral was bonded to the box and the grounding electrode conductor connected to it. In most cases today the service will be the usually place for bonding the neutral to the panel.

Maybe a more specific explanation would help here.
 

jeremy.zinkofsky

Senior Member
Location
nj
Basically, you want to create the shortest path to ground for current in case of a fault of any kind. If you connect all of the electrical devices, metal enclosures, etc to a single point by use of a green (grounding) wire, then you will give fault current only one path to earth ground. That is why the grounding electrode AND the neutral (grounded) conductor get connected in the main point of service and nowhere else. Everywhere else, the neutral and the ground are separated. That being said, lets say that you install a subpanel and use that little green screw to bond the neutral bar to the enclosure. What you have just done is created a second path to ground that acts as sort of a dead end for fault current. That subpanel does not have a good path back to earth so the fault will keep searching and possibly cause damage to a large part of the electrical system while trying to find the shortest path to ground.
 

jumper

Senior Member
Basically, you want to create the shortest path to ground for current in case of a fault of any kind. If you connect all of the electrical devices, metal enclosures, etc to a single point by use of a green (grounding) wire, then you will give fault current only one path to earth ground. That is why the grounding electrode AND the neutral (grounded) conductor get connected in the main point of service and nowhere else. Everywhere else, the neutral and the ground are separated. That being said, lets say that you install a subpanel and use that little green screw to bond the neutral bar to the enclosure. What you have just done is created a second path to ground that acts as sort of a dead end for fault current. That subpanel does not have a good path back to earth so the fault will keep searching and possibly cause damage to a large part of the electrical system while trying to find the shortest path to ground.

Ugh.:happysad:

Electricity wants to go back to its source not to ground(earth).
 
Basically, you want to create the shortest path to ground for current in case of a fault of any kind. If you connect all of the electrical devices, metal enclosures, etc to a single point by use of a green (grounding) wire, then you will give fault current only one path to earth ground. That is why the grounding electrode AND the neutral (grounded) conductor get connected in the main point of service and nowhere else. Everywhere else, the neutral and the ground are separated. That being said, lets say that you install a subpanel and use that little green screw to bond the neutral bar to the enclosure. What you have just done is created a second path to ground that acts as sort of a dead end for fault current. That subpanel does not have a good path back to earth so the fault will keep searching and possibly cause damage to a large part of the electrical system while trying to find the shortest path to ground.

We have all been there. I would recommend watching this so you can get this straightened out: Mike holt talking about grounding myths

http://youtube.com/watch?v=qNZC782SzAQ
 

roger

Moderator
Staff member
Location
Fl
Occupation
Retired Electrician
Basically, you want to create the shortest path to ground for current in case of a fault of any kind. If you connect all of the electrical devices, metal enclosures, etc to a single point by use of a green (grounding) wire, then you will give fault current only one path to earth ground. That is why the grounding electrode AND the neutral (grounded) conductor get connected in the main point of service and nowhere else. Everywhere else, the neutral and the ground are separated. That being said, lets say that you install a subpanel and use that little green screw to bond the neutral bar to the enclosure. What you have just done is created a second path to ground that acts as sort of a dead end for fault current. That subpanel does not have a good path back to earth so the fault will keep searching and possibly cause damage to a large part of the electrical system while trying to find the shortest path to ground.

Are you serious?

Roger
 

roger

Moderator
Staff member
Location
Fl
Occupation
Retired Electrician
The confusion caused by the electrons starting down a path running into other electrons coming back after finding it a dead end is what creates standing waves and high peak voltages.

:angel:

Ohhhhhhhhh! :D

Roger
 

kwired

Electron manager
Location
NE Nebraska
Basically, you want to create the shortest path to ground for current in case of a fault of any kind. If you connect all of the electrical devices, metal enclosures, etc to a single point by use of a green (grounding) wire, then you will give fault current only one path to earth ground. That is why the grounding electrode AND the neutral (grounded) conductor get connected in the main point of service and nowhere else. Everywhere else, the neutral and the ground are separated. That being said, lets say that you install a subpanel and use that little green screw to bond the neutral bar to the enclosure. What you have just done is created a second path to ground that acts as sort of a dead end for fault current. That subpanel does not have a good path back to earth so the fault will keep searching and possibly cause damage to a large part of the electrical system while trying to find the shortest path to ground.

Ugh.:happysad:

Electricity wants to go back to its source not to ground(earth).
We also want to provide a low impedance path back to the source to allow high amount of current to flow when there is a fault from an ungrounded conductor, which causes faster operation of overcurrent devices then if there wasn't a low impedance path. We connect to ground for reasons outside of fault currents, but the fact we do ground means some fault current may travel through ground to get to the source simply because a path is there.
 
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