100 amp sub panel question

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smviveiros

Member
Location
Providence, RI USA
I am looking to add a 100 amp sub-panel for a customer. The 200 amp panel in the basement is completely full.The customer dosn't want holes in the house and is fine with me running an underground line over to his attached garage. I was thinking I could just replace the meter socket outside or buy a feed through lug kit for the meter socket and nipple to a disconnect then run my line 120' away to the garage. But i'm having trouble finding a feed through kit and if this is even possible. hopefully someone can help?
 
Dennis Alwon

Dennis Alwon

Moderator
Staff member
Location
Chapel Hill, NC
Occupation
Retired Electrical Contractor
If you replace the meter with a 320 amp meter base then you will have double lugs. on them. You would need to make sure that the lugs will go as small as a 100 amp wire or you may have to increase the size at the meter.

Personally I would add a small sub in the basement and run a new line from there. I understand the owner does not want any holes but the hole will be filled with a conduit.

Call the manufacturer of the meter base that you have and see if double lugs are available. The other alternative is to bug onto the service conductors going into the house.
 
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smviveiros

Member
Location
Providence, RI USA
Right now the neutral bonding jumper is in the 200 amp main panel in the basement. When I add the disconnect outside I was going to isolate the neutrals and grounds for the sub. I am trying to avoid extra expenses for the homeowner because he is good client of mine. So if I upgrade the meter socket to a 320 then I'm going to have to change the drop to the house. I would like to maintain the existing 200amp in the basement and simply add the disconnect outside next to the meter for the sub in the garage. that's a good idea about finding a lug kit from the manufacturer. I going to the supply house today to see what they have.
 
kwired

kwired

Electron manager
Location
NE Nebraska
smviveiros said:
Right now the neutral bonding jumper is in the 200 amp main panel in the basement. When I add the disconnect outside I was going to isolate the neutrals and grounds for the sub. I am trying to avoid extra expenses for the homeowner because he is good client of mine. So if I upgrade the meter socket to a 320 then I'm going to have to change the drop to the house. I would like to maintain the existing 200amp in the basement and simply add the disconnect outside next to the meter for the sub in the garage. that's a good idea about finding a lug kit from the manufacturer. I going to the supply house today to see what they have.
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The disconnect is not required. Run your "service" conductors to from the garage to the meter. Your only remaining problem is how to terminate which you needed to do anyway.
 
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smviveiros

Member
Location
Providence, RI USA
I just realized when I wrote "now I need to upgrade the service drop" that I actually don't have to sorry about that. I am thinking that is going to be the way to go now. I need the disconnect outside for the sub because of the distance away from the meter I thought
 
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kwired

kwired

Electron manager
Location
NE Nebraska
smviveiros said:
I just realized when I wrote "now I need to upgrade the service drop" that I actually don't have to sorry about that. I am thinking that is going to be the way to go now. I need the disconnect outside for the sub because of the distance away from the meter I thought
Click to expand...

The meter is just a point in the service conductors. If your feed to the garage comes directly from the meter those conductors are still service conductors. Once you enter a building you have some limitations before you have to hit an overcurrent device.
 
Smart $

Smart $

Esteemed Member
Location
Ohio
kwired said:
The meter is just a point in the service conductors. If your feed to the garage comes directly from the meter those conductors are still service conductors. Once you enter a building you have some limitations before you have to hit an overcurrent device.
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He said in the OP that the garage is attached.
 
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GearMan

Member
Location
WI
smviveiros said:
I am looking to add a 100 amp sub-panel for a customer. The 200 amp panel in the basement is completely full.The customer dosn't want holes in the house and is fine with me running an underground line over to his attached garage. I was thinking I could just replace the meter socket outside or buy a feed through lug kit for the meter socket and nipple to a disconnect then run my line 120' away to the garage. But i'm having trouble finding a feed through kit and if this is even possible. hopefully someone can help?
Click to expand...

Replace the socket with this.http://docs.docstoc.com/pdf/20647643/e8f2b714-c0c2-4f6c-bdbb-78646e3a5f93.pdf The feed through lugs can feed the basement panel and a 100/2 cb in this unit can feed the garage. Very common item for us.
 
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hurk27

Senior Member
Location
Portage, Indiana NEC: 2008
Have you done a load demand calculation to see if the added load can still be served by a 200 amp service? (I question this as you said the 200 amp panel is full)

I second that you have a problem with the requirement of the grouping of the service disconnects required in 230.72 which the Midwest meter main would solve if you have the room, which is the same reason you can't use the suggestion that kwired posted in post #6 again because it would violate 230.72 (which would be allowed for a detached building)

I believe that someone also makes a meter main with just a 200 amp and 100 amp, but I couldn't find one when I started a job I'm doing now as in this case I have a dwelling over a small store where I needed a single meter with a 100 amp for the dwelling and a 200 amp for the store, so with the owners blessing (because of the cost of the meter main panel) I opted for two disconnects off the meter base (320) Photos in post 23 of this thread

Very few 200 amp meter bases have studs for changeable lugs, so finding one to install double lugs can be a challenge although I have installed them I think they were Durham something (Not sure of the spelling) but they are not a common meter in this area since the utility quit supplying meter bases, now Milbank or Midwest is the most common available. Square D has options but they are pricey also.

Not many options if the home owner wont allow you to run back up and out of the 200 amp panel.

And Welcome to the forum:thumbsup:
 
kwired

kwired

Electron manager
Location
NE Nebraska
Smart $ said:
He said in the OP that the garage is attached.
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Somehow I missed that, and thought we were discussing detached garage, sorry.

iMuse97 said:
Which means he needs the disco for the garage feeders to be grouped with the disco for the main service panel, which fact, I presume, was your implication.
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Absolutely correct.

GearMan said:
Replace the socket with this.http://docs.docstoc.com/pdf/20647643/e8f2b714-c0c2-4f6c-bdbb-78646e3a5f93.pdf The feed through lugs can feed the basement panel and a 100/2 cb in this unit can feed the garage. Very common item for us.
Click to expand...
Exactly what I would probably use, or Milbank version of same thing.

hurk27 said:
120 feet to an attached garage? just how big is this house?
Click to expand...

If following perimeter of a building distance adds up fast if you are going to the far side vs routing through building to get to same point.
 
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