[RE-wrenches] load side taps and NEC 240.21

[Allan Sindelar]

Mark,
Wait a minute...I may be wrong here, as I have become the "graybeard guy who
handles off-grid and weird stuff" at Positive Energy, but I think the 2008
Code allows 120% for commercial, not just residential, as long as it is fed
at the bottom of the bussbar. 2011 NEC is trying to make it a bit less
confusing by adding a set of alternatives.
Allan at Positive E
 
 
-----Original Message-----
From: re-wrenches-bounces at lists.re-wrenches.org
[mailto:re-wrenches-bounces at lists.re-wrenches.org] On Behalf Of Mark Frye


"Dwelling Unit. A single unit, providing complete and independent living
facilities for one or more persons, including permanent provisions for
living, sleeping, cooking, and sanitation."

From: re-wrenches-bounces at lists.re-wrenches.org
[mailto:re-wrenches-bounces at lists.re-wrenches.org] On Behalf Of Mark Frye

120% allowance is only "..For a dwelling unit....".
 
Clearly this is a load side Point of Connection. If it is a "dwelling unit""
then the 120% allowance is applicable. If it is not a "dwelling unit", then
there is no room to connect under NEC 2008.


  _____  

From: re-wrenches-bounces at lists.re-wrenches.org
[mailto:re-wrenches-bounces at lists.re-wrenches.org] On Behalf Of August Goers
 

Jerry - 

A line tap typically occurs between the utility meter and the main breaker -
not after the main breaker on the load side. It seems that you are
describing a load side tap which follows the 120% rule under 2008 NEC; I
might be misunderstanding the situation. Please clarify. There are few folks
out there who are able handle these large commercial grade interconnections
and I think it is well worth discussing.

From: William Miller wrmiller at charter.net

Jerry:

At a recent John Wiles seminar, John declared that this scenario is not a 
tap and is therefore not covered under the tap rule. This was news to me, 
but Wiles is considered some sort of guru in compliance discussions.

William Miller

>Wreches,
>
>
>I have a system where we are tapping onto the bus bars of a 1200 amp panel 
>fed by a 1200 amp main breaker. The easy place to tap onto the bus bars 
>is the load side of the breaker using the existing bolts.
>
>
>The inverter and utility fused disco are about 200 ft away, and the tap 
>conductors travel about15ft in EMT conduit before leaving the 
>building. After that the circuit is outdoors. NEC 240.21(B)5 allows taps 
>of unlimited length for conductors located outside of a building, except 
>at the point of load (in this case supply) termination.
>
>
>Can 20ft of conductor inside the building be covered by being "at the 
>point of load termination", or do I have to comply with NEC 240.21(B)2 and 
>have an OCPD within 25'?
>
>
>The construction foreman for this project is buddies with the inspector, 
>so getting a signed permit won't be a problem but I want this to be a code 
>compliant system. Can anyone lend some insight to the spirit of 
>240.21(B)2 and 5?
>
>
>Sorry if this has been discussed before, but searching didn't yield any 
>results.
>
>
>Best,
>
>Jerry Caldwell

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