Replies

1. 
   MSA1 | Sep 17, 2007 12:37am | #1

   If i'm reading you correctly I can explain some of this. When you require a seperate disconnect from the main, the main (in essence) becomes a subpanel so it needs a seperate ground (4 wire) and the neutrals and grounds need to be on seperate buses in the main (just like a subpanel).

   As far as the new meters, When I do a house around here (detroit area) edison will replace the meter. As far as I know I have not incurred any extra cost for the new meter. Your meters may be old enough to need replacement.

   Finally, you need to be able to disconnect service to the whole house. if the panel is 60' from the meter shutting off the main will still allow energized wire in the house. That is why you need the disconnect.

   Isnt this fun? :>)

   
   

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   Edited 9/16/2007 5:37 pm ET by MSA1

2. 
   edlee | Sep 17, 2007 12:53am | #2

   I don't understand why I can't have two regular old meters on the back of the house and a service cable running from each to the respective panels, with grounding and main disconnect at the panel.

    

   It's called "grouping of disconnects". All of the power in the building has to be able to be shut off from one location. If you want the code section I'll root around for it.

   Ed

3. 
   BillHartmann | Sep 17, 2007 01:10am | #3

   It might be possible that you existing panel is illegal. In general you can only have minimal amount of unprotected wiring INSIDE the house. Some places that is just through the wall into the panel. Others will allow a 3-6 ft.

   But if much of that 60 ft is within the house it does not meet current code and any modifications, at all, would requqire an change to fix it.

   I have not heard all of the fine print, but I don't think that the electrical code has any requirement requiring two meters.

   But that could be a POCO or local zoning reqquirement.

   .
   .
   A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.
1. 
   Clear_River_Construction | Sep 17, 2007 01:58am | #4

   if there is more than say, 5' of Service Entrance Cable inside, a disconnect would be required at that pointand then, since the disconnect is now the Service Equipment, yes ... an Insulated Neutral, and no bonding at the now Sub Panel ....didn't we just discuss this ..??

1. 
   BillHartmann | Sep 17, 2007 02:26am | #5

   "if there is more than say, 5' of Service Entrance Cable inside, a disconnect would be required at that point"5 ft might be way too much.As I said it depends on the AHJ.This is what the handbook says about it."No maximum distance is specified from the point of entrance of service conductors to
   a readily accessible location for the installation of a service disconnecting means. The
   authority enforcing this Code has the responsibility for, and is charged with, making
   the decision as to how far inside the building the service-entrance conductors are
   allowed to travel to the service disconnecting means. The length of service-entrance
   conductors should be kept to a minimum inside buildings, because power utilities
   provide limited overcurrent protection. In the event of a fault, the service conductors
   could ignite nearby combustible materials.
   Some local jurisdictions have ordinances that allow service-entrance conductors to run
   within the building up to a specified length to terminate at the disconnecting means.
   The authority having jurisdiction may permit service conductors to bypass fuel storage
   tanks or gas meters and the like, permitting the service disconnecting means to be
   located in a readily accessible location.
   However, if the authority judges the distance as being excessive, the disconnecting
   means may be required to be located on the outside of the building or near the building
   at a readily accessible location that is not necessarily nearest the point of entrance of
   the conductors. See also 230.6 and Exhibit 230.15 for conductors considered to be
   outside a building."And some local amendments require ALL service disconnects to be external..
   .
   A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.

2. 
   Chargerny | Sep 17, 2007 06:43am | #6

   Thank you all three. It's beginning to make sense. The single point of cut-off is the key I guess.In answer to specific points, the 60' of 3-wire service cable currently runs along the outside of the house. Within a foot of it entering the basement it's in the main panel. And I believe the separate meter for each unit is mandated by New York State building code.