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Joined: May 2003
Posts: 14
B
Junior Member

Alan I just re-read all the post and we are saying the same thing.


Last edited by BGaquin; 05/14/07 12:14 PM.
BGaquin #163677 05/14/07 01:15 PM
Joined: Jul 2004
Posts: 9,923
Likes: 32
G
Member
It is pretty standard to see the GEC made up in the meter base around here and that will also be bonded to the grounded conductor. We also have a main bonding jumper in the service disconnect. That us usually fed with 3 wire in plastic pipe to avoid the "parallel neutral" problem.


Greg Fretwell
Alan Nadon #163699 05/15/07 06:53 AM
Joined: Mar 2007
Posts: 8
E
Junior Member
Originally Posted by Alan Nadon
In my opinion, the grounded conductor needs to be bonded at all points ahead of the service disconnect. This allows a fault to take the shortest path back to the source of power.
If I follow your description a fault in the meter socket would mean the conduit and neutral/ grounded conductor would take the fault into the building to the main panel bond before allowing the fault to go to the transformer or souce. A fire waiting to happen.
Alan--


I got busy and got away from this post. I better clarify my situation and question.

I had a seperate meter socket and 100 amp disconnect (2 enclosures) on the outside of the home. The GC and ground were bonded at the meter socket and again in the disconnect. From the disconnect I ran 3 wire to the original panel inside the home and treated it as a sub. Installed a ground bar, isolated neutral and grounds and removed the old bonding screw from the neutral bar. I'm new at decribing this stuff in writing so please bare with me.

The ahj had no problem with any of this except the fact that I had cut (terminated) the neutral in the outside disconnect. He wanted me to run the neutral (bonded but uncut) direct to the panel inside the house. What I didn't understand was why would I treat the neutral any different in this (new) main panel just because it is now on the outside of the house. I used a Siemans 100 amp weatherproof disconnect and it did not have a "lay-in" type lug as you have in a meter socket. He Ok'd the install with the above caveat.

I will be running into him again since I will be doing more work in this town and want to have my ducks in a row.

I apoligize again for my poor description but I'm just wanting to learn.

Thanks,

electricianjeff

Joined: Mar 2005
Posts: 399
A
Member
Jeff, Your description appears to be in compliance with the Code.
Three wire to the sub panel and seperated grd. & Neutrals.
Using conduit for the ground path from the service disconnect to the distribution panel is a design consideration, but does comply.
Ask the AHJ about the neutral and his reasoning.
We all want to know.
Alan--


Alan--
If it was easy, anyone could do it.
Alan Nadon #163712 05/15/07 01:17 PM
Joined: Nov 2000
Posts: 2,148
R
Member
Jeff,
What are you using for the equipment grounding conductor if you ran only 3 wires?
Don


Don(resqcapt19)
resqcapt19 #163734 05/15/07 09:22 PM
Joined: Mar 2007
Posts: 8
E
Junior Member
Originally Posted by resqcapt19
Jeff,
What are you using for the equipment grounding conductor if you ran only 3 wires?
Don


The path to ground would be via the 1 1/4" rigid conduit. Is there a better way to design this. If so, please fill me in on the details. I will be doing more of these.

Thanks,
ElectricianJeff

Joined: Mar 2005
Posts: 399
A
Member
Jeff,
Metal conduit has historically been used as a ground path. It is also notorious for causing problems when not properly installed. Loose joints, connectors or lock nuts, not making good contact, lack of bonding bushings or bonding lock nuts, can all contribute to an ineffective ground path.
Corrosion and rust can also negate the metal conduit as a ground path.
Although more expensive, many contractors will install a ground conductor sized from 250.66 (service) or 250.122 (sub panel) as a means of insuring an effective ground path.
Alan--


Alan--
If it was easy, anyone could do it.
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