Service equipment neutral to ground
- Thread starter cppoly
- Start date
- Status
- Location
- Massachusetts
Yes.
kwired
Electron manager
- Location
- NE Nebraska
- Occupation
- EC
In the right conditions yes. Most of the time there is no direct low impedance path back to the source other then the grounded service conductor.
mwm1752
Senior Member
- Location
- Aspen, Colo
Current will take all paths -- the path back to the transformer is thru the service lateral grounded conductor not sure how you would find a path to transformer grounding point thru the metal enclosure
- Location
- Massachusetts
No danger as long as the grounding and bonding are all proper and intact.
mwm1752
Senior Member
- Location
- Aspen, Colo
The current does not flow to the grounding electrode in earth as a path
- Location
- Massachusetts
We cannot use it as a path but it is one.
mwm1752
Senior Member
- Location
- Aspen, Colo
I am keeping the conversation to unbalanced load return path & power source grounding point -- of course the electrode system is the path to direct induced voltage on wiring systems from lighting strikes to earth
- Location
- Massachusetts
But you seem to be saying if I drive a ground rod into the earth and connect it to a neutral conductor carrying unbalanced current there will be no current flow to earth. :?
mwm1752
Senior Member
- Location
- Aspen, Colo
the flow goes back to the source & earth is not a source -- the same reason the electrode will not trip a breaker -- show me a diagram of your thoughts -- simply if there is a current flow & your break the connection/ tap the buss & you will see an arc occurs. now take you electrode conductor & do the same thing/ no arcs -- now we can get into the resistance differentials & path continuity & really have conversation.
You do realize that the utility utilizes an MGN don't you?.
Look at the little video in the link below and consider the water pipe common to the GES
http://www.codecheck.com/cc/TheFatalCurrent.html
Roger
Earth may not be THE source but because there's another electrode connected to the neutral at the service transformer, the earth is a path... albeit a higher impedance path than a nominally functional neutral conductor, but it is a path (though not to be considered one under Code) and will conduct some amount of current.
- Location
- Massachusetts
I agree with that, Roger and Smart have expressed my thoughts on the current flow and the reasons for it.
- Occupation
- Licensed Electrician
I like to call it the unavoidable objectionable current.
See the attachment. If there unbalanced neutral current returning to the utility source, the neutral is connected to the ground bar which is connected to the service equipment metal case. So some current should be flowing here (I think?).
Edit: Hmm there is a image limit of 620 x 280 which makes the picture almost illegible. I can't upload it.
Edit: Hmm there is a image limit of 620 x 280 which makes the picture almost illegible. I can't upload it.
Attachments
Last edited:
- Occupation
- Licensed Electrician
Yes. That is not in dispute.
Per attachment, no current is flowing "through" the enclosure. The grounded service conductor and earth through the two electrode systems are the only paths depicted.
Michael15956
Senior Member
- Location
- NE Ohio
Maybe this will help you understand it. Current will take all paths available, but only if the path is connected to the source.
Under normal conditions the metal case is connected to its' source by two ways, the neutral/grounded conductor and by the grounding electrode. Once again, and as stated before, under normal conditions the grounding electrode is a poor conductor. So since the only path connected to the source is the neutral there is no current on the metal case.
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