# Do I have to upgrade the underground feeder?



## B-ri (Dec 11, 2013)

Here's the scenario:

4300 sq-ft house, customer is turning it into a two family. Moving the meters outside I will have one for each unit plus a common.

The existing underground feeders are 1/0 copper which go into the house and hit a can, then are splice onto 3/0 copper conductors and piped to a 200 amp main disconnect, from there they go to the meter then panel.

Are the feeders undersized? Or does the 83% apply to this scenario?

Also, does splicing the 1/0cu onto the 3/0cu make it ok for the 75* c termination?

Thanks in advance


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## telsa (May 22, 2015)

Three (3) meters for such a simple scheme -- is odd. 

One would presume that the 'landlord' is going to be living in one of the units... or?

You're proposing to simply SPLIT a load in half -- not increase its size. So it's hard to understand -- until you perform a load calc -- why the service lateral need be touched.

One might effect the same result by just sub-metering. ( D-mon)

Just not enough info to dope out which way to turn... but a fresh load calc would seem in order.


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## MDShunk (Jan 7, 2007)

Who owns the u/g feeder? What you describe makes me wonder if they're PoCo owned and sized to NESC rules.


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## B-ri (Dec 11, 2013)

telsa said:


> Three (3) meters for such a simple scheme -- is odd. One would presume that the 'landlord' is going to be living in one of the units... or? You're proposing to simply SPLIT a load in half -- not increase its size. So it's hard to understand -- until you perform a load calc -- why the service lateral need be touched. One might effect the same result by just sub-metering. ( D-mon) Just not enough info to dope out which way to turn... but a fresh load calc would seem in order.


The house is basically already wired for two units(2 kitchens,etc,etc). He will be living in one unit, but wants the bills separate. Load calc checked out fine.

But I'm getting mixed answers on if the underground feeder is undersized for 200A


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## B-ri (Dec 11, 2013)

MDShunk said:


> Who owns the u/g feeder? What you describe makes me wonder if they're PoCo owned and sized to NESC rules.


Spoke with them today, homeowners problem


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## MDShunk (Jan 7, 2007)

B-ri said:


> Spoke with them today, homeowners problem


Your load calc didn't come out to "200 amps". What's your load calculation result? 

The load's not really changing anyhow. When one house is splint into two (very common), the load stays damn near the same. My own thoughts... it was fine all these years without any voltage drop issues, I assume.


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## papaotis (Jun 8, 2013)

if the same load is split, it should be fine, except to local rules.


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## MTW (Aug 28, 2013)

Which poco are you dealing with? Since you said the customer owns it, I'm guessing it's Nstar or National Grid?


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## MDShunk (Jan 7, 2007)

Cold sequence metering a 200 amp service for a house is strange as hell too. Something tells me there's more to this than meets the eye. Some sort of history.


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## telsa (May 22, 2015)

My Plan A would be to use D-mon sub-metering when and where needed -- and just pass on the tab.

1) Commons -- split -- say 50:50

2) Tenant -- pays the pro rata of the bill based on his kWHrs versus the Poco tab.

{ He's not going to re-plumb the building to split the water and sewer tab. }

Then you can skip a lot of complications. 

Perhaps you'd just set a buddy panel next to the current panel and shift the circuits that matter -- over. 

If the CTs are cheap enough, you might just tackle the matter that way, not even setting a sub-panel. 

( You can get away with nesting multiple (branch) hots under one CT. Parallel amps are still amps. This nesting could even be done inside the existing panel. )

http://www.emon.com/

It's not the only game in town -- but is a big player.

Poke around for ideas.

Digging up the Service Lateral is a PITA almost every time. 

Lots of fees to the Poco -- not so many to you.


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