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Posted By: johnd24 300 amp. resi. service - 10/24/03 01:28 AM
Has anyone ever installed a 300 amp. service for a new single family dwelling.If so can i parellel 4/0 alum. to line side of meter socket....can i come off of load side of meter socket with 4/0 alum to feed my 200 amp. m.b. panel and #2 off of load side of meter socket to feed my 100 amp. m.b. panel.
Of course using double lugs.
Thanks !!!!!
Posted By: Ryan_J Re: 300 amp. resi. service - 10/24/03 01:52 AM
Unless I'm reading this wrong, I would say you're O.K. The only thing I'm wondering is where your disconnects for the service entrance conductors will be. Aslo, as you describe it, be aware that you will need a 1/0 grounding electrode conductor, not a number 2. By the way, I've never seen a 300 amp panel...who makes it?
Posted By: johnd24 Re: 300 amp. resi. service - 10/24/03 02:14 AM
The panels with main breakers will be located within 3' of the meter socket,in the basement of the home.One will be a 200 amp. main breaker panel the other right next to it will be a 100 amp. main breaker panel.
#2 is not the grounding electrode conductor,its the load side of the meter socket to my 100 amp. panel.
I will have double lugs in my meter socket 1 set of lugs will have 4/0 alum. wire for the 200 amp. panel,the other set of lugs will have # 2 alum. for the 100 amp. panel.
Posted By: Ryan_J Re: 300 amp. resi. service - 10/24/03 02:27 AM
I think you'll be O.K.

BTW: I understood what you meant with the number 2, I was just sizing the GEC by the combined circular mills of the service entrance conductors for my own practice as much as anything.
Posted By: Fred Re: 300 amp. resi. service - 10/24/03 04:20 AM
See 250.66(A)for GEC size. If the electrode is rod, pipe or plate, and is the sole connection, #6 cu or #4 al.
Posted By: johnd24 Re: 300 amp. resi. service - 10/24/03 10:26 PM
Thanks again guys !!!!
Posted By: e57 Re: 300 amp. resi. service - 11/04/03 05:51 AM
I have to do one next week..... Around here we do it as a 320a service*, 2- 200a feeder. It comes as a single package meter/main combo. The two main cb's can be swaped out for whatever you like, under 200a of course.
B-line makes them, and I think Cut Ham does too. (* our Utility here frowns on any single residence getting a 400a service, but they allow this. )
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