legal or not

[rickl]

can you experts tell me if this is legal or ever been legal.
older home probably built in 1940'-50' 3850 sf with small 600 sf detached apartment. 200 amp overhead service hits meterbase on side of house then go's into basement all in rigid conduit, wire size 2/0 copper. in the basement it go's into a 6"x6"x2' gutter where it is tap to feed one 200 amp panel & one 100 amp panel. i think the service entrance conductor should be sized for 300 amp. i did a load calc i came up with 207 amps. its a kitchen remodel job not adding much in load, a couple of can lights & refeeding appliances at there new locations. i'm recommending upgrading the service to a 320 amp.
thanks for any input

 

[Smart $]

I would say it was legal at the time it was installed (though before I existed).

 

[iwire]

Having the 2/0 coper supply a 200 and 100 amp service panel is 'legal' today.

See 230.90(A) Exception No. 3.

However the the calculated load must not exceed the ampacity of the conductors.

Your 2/0 copper is most likely rated 175 amps.

Time for a 400 amp service with a class 320 meter.

Of course you could leave the existing panels, replace the meter socket with a class 320 and replace the conductors with 4/0 copper for a rating of 230 amps.

 

[izak]

Bob, what you said about 2/0 being good for 175 amps makes me wonder about something..

table 310.15 B 6 tells us that we can use 2/0 copper for services on single family dwellings..

does that mean that i can use that 2/0 for the riser AND between the meter and first point of disconnect, or just the riser (mast) ?

and on hooking up mobile homes, generally we set a pole with a meter/main combo, and pull 4 wires underground to the mobile home. on a 200 amp service, can we pull 2/0 between that disconnect and the mobile home, or should it be 3/0 ?