Parallel path for neutral current?

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Steelhead said:
Would it be safer for a plumber/homeowner if I were to move the GEC from the sub panel to the disconnect in the meter pedestal? The end result would be the GEC connected to the grounded conductor terminal at the disconnect and then terminated to the galvanized piping in the house probably down by the meter where the supply from the city enters the basement. Thoughts?
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It would be safer only in the context of the connection being two terminations closer to the source. Safeness is dependent on where the fault occurs. If it occurs somewhere other than at or between these two terminations, essentially no difference.

I believe it is compliant as it is now for existing installations. If you relocate as suggested, it's my opinion you would also have to run an EGC to the subpanel and isolate its grounded conductors and EGC's. Where's the MBJ?
 
Smart $ said:
It would be safer only in the context of the connection being two terminations closer to the source. Safeness is dependent on where the fault occurs. If it occurs somewhere other than at or between these two terminations, essentially no difference.

I believe it is compliant as it is now for existing installations. If you relocate as suggested, it's my opinion you would also have to run an EGC to the subpanel and isolate its grounded conductors and EGC's. Where's the MBJ?
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That's what my first thoughts were when I originally saw the existing setup. To be honest I completely forgot to look to see where the MBJ was. I will need to stop by there later this week so I will look then. Merry Christmas by the way!
 
Smart $ said:
See 250.32(B) Exception

Merry Christmas !!!
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I think that I was unclear with my last post. What reference would allow me to run an EGC, separate of the supply conductors, to the subpanel so I essentially have a four wire system to the subpanel? I'm not seeing anything except for the exception for receptacles?
 
Steelhead said:
I think that I was unclear with my last post. What reference would allow me to run an EGC, separate of the supply conductors, to the subpanel so I essentially have a four wire system to the subpanel? I'm not seeing anything except for the exception for receptacles?
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250.32(B) requires a four wire feed for nearly everything other than existing installations.

It sounds like you are trying to eliminate the code required objectionable current on the water pipe. You can't if the water pipe meets the criteria for a grounding electrode unless you dig up the water line and insert a dialectic coupling or something similar.
 
ActionDave said:
250.32(B) requires a four wire feed for nearly everything other than existing installations.

It sounds like you are trying to eliminate the code required objectionable current on the water pipe. You can't if the water pipe meets the criteria for a grounding electrode unless you dig up the water line and insert a dialectic coupling or something similar.
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What I wanted to do was to run an EGC to the subpanel to make it a four wire feed, but I don't think that I can run an EGC separate of the supply conductors currently running to the subpanel without violating the code, unless there is a provision that I am unaware of that would allow this. Then I would connect a GEC to the water pipe from the grounded terminal at the disconnect which is outside in the meter enclosure. That way the water pipe would still be used as a grounding electrode.

All this being said I don't have to do any of this (making this a four wire system) - I could just leave it the way it was originally installed 20 plus years ago and not lose any sleep over it. I just wanted to know that I could modify this current setup and be code compliant if the need were to arise, etc.
 
Steelhead said:
What I wanted to do was to run an EGC to the subpanel to make it a four wire feed, but I don't think that I can run an EGC separate of the supply conductors currently running to the subpanel without violating the code, unless there is a provision that I am unaware of that would allow this. Then I would connect a GEC to the water pipe from the grounded terminal at the disconnect which is outside in the meter enclosure. That way the water pipe would still be used as a grounding electrode.

All this being said I don't have to do any of this (making this a four wire system) - I could just leave it the way it was originally installed 20 plus years ago and not lose any sleep over it. I just wanted to know that I could modify this current setup and be code compliant if the need were to arise, etc.
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I agree with your assessment.

To bring into current Code compliance, you'd have to replace the SE cable with a 4-wire SER, install another ground rod, make sure MBJ and GEC connections are in the pedestal, and isolate the EGC and grounded conductors at the subpanel.
 
Smart $ said:
I agree with your assessment.

To bring into current Code compliance, you'd have to replace the SE cable with a 4-wire SER, install another ground rod, make sure MBJ and GEC connections are in the pedestal, and isolate the EGC and grounded conductors at the subpanel.
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Thanks for your help Smart $.
 
Steelhead said:
What I wanted to do was to run an EGC to the subpanel to make it a four wire feed, but I don't think that I can run an EGC separate of the supply conductors currently running to the subpanel without violating the code, unless there is a provision that I am unaware of that would allow this. Then I would connect a GEC to the water pipe from the grounded terminal at the disconnect which is outside in the meter enclosure. That way the water pipe would still be used as a grounding electrode.

All this being said I don't have to do any of this (making this a four wire system) - I could just leave it the way it was originally installed 20 plus years ago and not lose any sleep over it. I just wanted to know that I could modify this current setup and be code compliant if the need were to arise, etc.
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Since your existing installation is type SEU cable, even if you ran a fourth conductor external to the cable, your neutral within the SE cable is still a bare conductor potentially creating problems with isolating it from the equipment grounding conductor, meaning it would still be better idea to replace the SEU cable with either SER, raceway methods, etc.
 
kwired said:
Since your existing installation is type SEU cable, even if you ran a fourth conductor external to the cable, your neutral within the SE cable is still a bare conductor potentially creating problems with isolating it from the equipment grounding conductor, meaning it would still be better idea to replace the SEU cable with either SER, raceway methods, etc.
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Makes perfect sense. Thanks! :D
 
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