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Joined: Oct 2002
Posts: 830
S
Member
An inside panel is already coming off the load side of meter. Customer said someone rold him he could come off of it again for another feed. I didn't think this could be done by code. Is he right? Thanks

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Joined: Jan 2005
Posts: 5,445
Likes: 2
Cat Servant
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Not sure of all the details you're facing, so I'll give a more generic response.

Today, we install services where there is a disconnect with a fuse / breaker right at the meter. This point is the "service," and is where the neutral and ground are to be bonded.

Older services are often a simple meter pan, with no way to disconnect power without pulling the meter. Others can argue whether this is 'legal' or not today- as far as I'm concerned, this is such a bad design that I won't do anything until it's changed.

Assuming that you have a disconnect at the meter, as well as overcurrent protection there, everything downstream is a "sub-panel." Keeping in mind the tap rules and feeder ampacities, there are many ways to power multiple panels. You can start with a panel at the service; you can feed through each and every panel until you get to the last one; or you can mix the two approaches.

The devil is also in the details. Very few load centers come with lugs that have any provision for multiple conductors; landing two wires under a lug just because they fit is not allowed.

Then there are those issues regarding bonding of the neutrals. Since few older panels have ground busses, and the neutral bus is often bonded to the case, you have an arrangement that cannot be made compliant with today's rules.

Under today's rules, you can have all manner of panel arrangements. For example, my own house was rewired with the following layout:

Meter feeds a main panel. Grounding electrode conductors and the neutral bond are in this panel.

The main panel feeds a local receptacle, as well as three other panels: the inside "primary" panel, the outside HVAC panel, and the outside deck panel.

The inside primary panel, in turn, has branch circuits- as well as feeding the kitchen panel and the bath/laundry panel.

The HVAC panel serves the mini-split air conditioner units (there are three), as well as a tiny panel in the carport storage area.

The deck panel serves the deck, as well as the (planned) hot tub, storage shed, and workshop.


Joined: Oct 2002
Posts: 830
S
Member
The house is only a few years old. There is a 200 amp meter base outside. It goes directly inside to the opposite wall inside to a 200 amp Main breaker panel. To do what the homeowner said someone told him, you would have to come off the same load lugs in the meter base that is feeding the inside panel. There is the catch. Unless the lugs in the meter base are approved for 2 wires, it can't be code compliant as far as I can see. I know older homes have it like that everywhere. Always checking though, I have been wrong once or twice:)

Joined: Jun 2004
Posts: 1,273
T
Member
The classic meter pan is one and done.

No Poco is going to give you permission to open it up to stuff extra feeders into their meter socket. None.

Most meter pans are so limited in space that one can't even squeeze a Polaris feeder tap inside.

&&&

It's a no brainer to simply set a sub panel using, say, a 100A stab-on breaker -- or to attach pass thru lugs -- again a factory produced stab-on product.

You'll have to dig around for it... C-H has these in 3-phase and 2-pole, 1-phase. They slap on like a C/B... but have no over current protection: just a set of lugs.

Such pass-thru lugs are typically rated up to 200 Amps at 240V.

And with that, your design task is complete.

You simply move at least 2 poles of C/Bs out and push on these pass thru lugs. They should lead to another, daughter panel (sub panel) with enough space to make everyone happy.

The Poco need not be consulted. You still have a 200 Service -- but with enough room for AFCI breakers aplenty.

The pass thru conductors need to stay fully sized for 200A. The daughter panel can have a Main or -- to save bucks -- just MLO.

If the daughter panel uses a back-fed Main push-on breaker -- figure it to be limited to 100A.

The NEMA players are protecting their market by not low balling push-on breakers beyond that size.



Tesla
Joined: Jul 2004
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G
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I have seen plenty of commercial services that come off the meter with a large conductor, into a piece of gutter and then splits out to a number of disconnects. I agree it is rare to find a meter base alone that can accommodate this kind of tap.


Greg Fretwell
Joined: Apr 2002
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A 400 rated, 320 continuous single phase meter pan hasdual 'load lugs', and it's common to have 2x200 amp panels (with 200 amp mains).

I have not seen any meter pan with lugs listed for multiple conductors.

A common method to accomplish a second panel is to install load conductors into a troff as Greg stated.


John
Joined: Apr 2013
Posts: 22
S
Member
Any time "someone told me it's ok", an alarm bell goes off for me. I learned a lot reading through all the posts. The most common solution I've seen is the one suggested by Tesla (pass through lugs, or a 2 pole push on breaker if the subpanel will be small).

Joined: Apr 2002
Posts: 7,381
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sedesigner1:
Are you saying that you have not seen a PSE&G 400/320, single phase meter pan?

I don't know what area of NJ you are from, but JCP&L also has an approved unit.


John

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