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Discussion Starter · #1 ·
I have a grounding question. I'm tapping a 200amp Feeder to a 100amp subpanel. The feeder has no equipment ground in it. Would the nuetral bar need to be isolated in this instance, like a main panel, or should it be bonded to the case?
 

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Are you tapping a feeder or service conductors?
A feeder SHOULD have a ground.
 

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Discussion Starter · #3 ·
It is a Feeder. Some sort of 3 conductor cable i've never seen before. Looks like Romex with 1/0 conductors enclosed. There is a 200amp disconect at the meter which feeds (via the 3 conductor cable) a 200amp panel in the house about 40feet away. The main panel is completely filled up, so I'm going to tap the Feeder(3 conductor cable) per Article 240 25ft tap rule. The cable has NO equipment ground.
 

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If the main disconnect is remote from the main panel a 3-wire feeder was allowed under certain circumstances for many years.

What code are you under? The 3-wire feeder allowance was dropped for 2008 and I couldn't say if this would be grandfathered.
I would check with your AHJ before doing this.
 

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I'd put a two-pole in the existing panel and do a four wire sub feed to a sub panel. I think checking with the AHJ is a good idea, but I also think if the 200 amp panel has a valid primary and secondary grounding wire, I think a sub panel would be appropriate.

I have never run into the setup you describe. Does the main disconnect have the primary and secondary grounds in it or are they at the panel and is the panel a main lug only or does it have a main breaker?
 

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Discussion Starter · #6 ·
I'd put a two-pole in the existing panel and do a four wire sub feed to a sub panel. I think checking with the AHJ is a good idea, but I also think if the 200 amp panel has a valid primary and secondary grounding wire, I think a sub panel would be appropriate.

I have never run into the setup you describe. Does the main disconnect have the primary and secondary grounds in it or are they at the panel and is the panel a main lug only or does it have a main breaker?
what do you mean by the "primary and secondary grounds"? Never heard this terminology.... The Main panel is completely full, no room for a two-pole, this is the reason I'm tapping off the Feeder. I'm thinking I need to bond the nuetral to the can, like the Main, to ensure a path for objectionable current. btw...there is no AHJ in this area.
 

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The Main panel is completely full, no room for a two-pole, this is the reason I'm tapping off the Feeder.
So install a sub-panel right next to the main and move some of the lesser circuits over to the sub to make room. :whistling2:



I'm thinking I need to bond the nuetral to the can, like the Main, to ensure a path for objectionable current.
Not with a sub-panel you don't. You MUST run a 4-wire feeder (in most cases, and all cases within the same structure) to a non-service panel (sub-panel). Neutrals and grounds are kept isolated.

A service entrance tap like you are proposing is another story.
 
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