Service 1200 amp

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triplex15

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WIth a 1200amp 120/240v Overhead service they are calling for 3 conduits with 500 mcm up to weather heads. Will the power company hook to parallel condutors. I need the best suggestion on how to procede with this. Thanks
 
You will have to check with the powercompany as to their requirements for taps. However 500kcmil thhn copper at 75c is only rated for 380 amps. 380 X 3 = 1140 amps. Can' tgo up to 1200 amps per section 240.4 (C). Conductors have to be equal or greater than the rating of the overcurrent device.
 
SEO said:
You will have to check with the powercompany as to their requirements for taps. However 500kcmil thhn copper at 75c is only rated for 380 amps. 380 X 3 = 1140 amps. Can' tgo up to 1200 amps per section 240.4 (C). Conductors have to be equal or greater than the rating of the overcurrent device.

I am not sure I agree

II. Overhead Service-Drop Conductors

(A) General. Conductors shall have sufficient ampacity to carry the current for the load as calculated in accordance with Article 220 and shall have adequate mechanical strength.
 
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Denis,
If the reference to 1200A service means that there is 1200A overcurrent protection, then 230.90(A) [NEC 2002 handy) says that the wires need to be rated equal or higher than the OCPD.
 
ron said:
Denis,
If the reference to 1200A service means that there is 1200A overcurrent protection, then 230.90(A) [NEC 2002 handy) says that the wires need to be rated equal or higher than the OCPD.

Maybe there is not a 1200A main. Then it might be ok. ????
 
ron said:
Denis,
If the reference to 1200A service means that there is 1200A overcurrent protection, then 230.90(A) [NEC 2002 handy) says that the wires need to be rated equal or higher than the OCPD.

Yeah I realized after I posted and too late to edit that I was may be in error. Where do the service conductors begin in this scenario? Does my quote say that the service drop can be smaller but the riser must be 1200 amp capacity? More confused now then before.
 
ron said:
C3PO,
If it isn't a 1200A main, then why call it a 1200A service?

What else would you call it?
What if it was a 1200A MLO with six 200A breakers in it and a calculated load of 1100A wouldn't that be ok with the 500kcmil sets?
 
triplex15 said:
Will the power company hook to parallel condutors. I need the best suggestion on how to procede with this. Thanks
You betcha, but they appreciate the head's up on how many of what gauge you have there. Most of the trucks won't have that many big taps in the bin. If they know ahead of time, they'll bring plenty.
 
triplex15 said:
WIth a 1200amp 120/240v Overhead service they are calling for 3 conduits with 500 mcm up to weather heads. Will the power company hook to parallel condutors. I need the best suggestion on how to procede with this. Thanks

You will need a GFI on your 1200A main, and need it tested (and witnessed)
 
If you read triplex15s post all he stated is that he has a 120/240 system that is overhead fed and it is going to be rated for 1200 amps. Everyone seems to assume that it is 3-phase. With the information provided about the only thing that I can say is that he isn't required by the NEC to provide GFIC protection and that he should check with his power company about the taps . Does he have one main or 6 mains? Is it 3 phase delta (being he mentioned 240 volts) or is it single phase? Not enough information.
 
SEO said:
If you read triplex15s post all he stated is that he has a 120/240 system that is overhead fed and it is going to be rated for 1200 amps. Everyone seems to assume that it is 3-phase. With the information provided about the only thing that I can say is that he isn't required by the NEC to provide GFIC protection and that he should check with his power company about the taps . Does he have one main or 6 mains? Is it 3 phase delta (being he mentioned 240 volts) or is it single phase? Not enough information.

I think that you meant GFPE? 230.95
 
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