millbank 320a series meter

[zachw45]

Installing service change from 200a to millbank 320a series meter that has 2 200a main breakers in it. The service is underground and is supplied from a tap box on the street which only has 350mcm al running in it. I have to refeed from the tap box to the house. art 310.15 tells me 350mcm al is good for 300a service and 500mcm al is good for 350a service. need some help on sizing wire.

 

[ryan_618]

Re: millbank 320a series meter

What is the computed load?

 

[tom baker]

Re: millbank 320a series meter

Residential or commerical?

 

[zachw45]

Re: millbank 320a series meter

It is a res single family service. There is no load at this time due to new adition plans still in the works.

 

[ryan_618]

Re: millbank 320a series meter

There must be a computed load, as per article 220. The reason I ask is that I believe 230.90(A), exception no.3 would be the governing section of the code.

MAybe Tom knows something I am missing...he usually does

 

[a.wayne3@verizon.net]

Re: millbank 320a series meter

Who did the underground the POCO ?????

 

[tom baker]

Re: millbank 320a series meter

For ampacity see 310.15(B)(6). for the meter to each panel if 200 Amps can use 4/0 Al, assmuming there will be 2 200 amp panels with mains.

 

[zachw45]

Re: millbank 320a series meter

Well the main breakers are built into the meter. 2 200a fed from load side of meter term. i am looking to size feeders from tap box to meter.

 

[pierre]

Re: millbank 320a series meter

As Tom has stated, use a calculated load as per 220. For the service conductors to the meter use table 310.15(B)(6) for the calculated size, then for the two 200 amp breakers from the meter as per the same table, 4/0 al to each breaker is permitted.

Pierre