Which is the Service Switch?

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I am preparing a report for a school that has a separate building (Mini-school) at the back. The main building is served by a 2000Amps service switch. The 2000Amps service switch feeds the Main Switchboard for the main building. The same service switch is also feeding a 600A fused disconnect switch located at the mini school. The 600A disconnect switch feeds panels located at the Mini-school. The Mini-school has a separate asset number therefore it’s considered a separate building. Which switch should I identify as the service switch for the Mini-school, the 2000 Amps located in the main building or the 600 Amps located at the Mini-school? Is there a code reference I can use for this?
 
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ceb58

Senior Member
Location
Raeford, NC
I am preparing a report for a school that has a separate building (Mini-school) at the back. The main building is served by a 2000Amps service switch. The 2000Amps service switch feeds the Main Switchboard for the main building. The same service switch is also feeding a 600A fused disconnect switch located at the mini school. The 600A disconnect switch feeds panels located at the Mini-school. The Mini-school has a separate asset number therefore it?s considered a separate building. Which switch should I identify as the service switch for the Mini-school, the 2000 Amps located in the main building or the 600 Amps located at the Mini-school? Is there a code reference I can use for this?

If you look under 230.2 it will tell you that your 2000amp is the service. Every thing after the service switch is a feeder. As far as identifying you can identify the 600amp disco. as stated in 225.37
 
If you look under 230.2 it will tell you that your 2000amp is the service. Every thing after the service switch is a feeder. As far as identifying you can identify the 600amp disco. as stated in 225.37

Thanks for the information.
Here is the sketch, I had forgotten to include the sketch it.
scan0002.jpg
 

infinity

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Staff member
Location
New Jersey
Occupation
Journeyman Electrician
What tap rule do the conductors fall under for the 600 amp switch in the main building? I see that the 600 has no OCPD.
 

jwelectric

Senior Member
Location
North Carolina
Is there a difference between ?main? and ?service disconnect??

In the drawing what I see is one 2000 amp service disconnect
One six switch panelboard not a main panelboard
One non-fused disconnect that may or may not be installed illegally. It would depend on the size of the conductors supplying and leaving the disconnect. Are the conductors rated at 2000 amps?
At the second building I see a 600 amp main disconnect not a service disconnect as the service disconnect is located at the first building although this main disconnect must be suitable as service equipment.
 

dbuckley

Senior Member
What tap rule do the conductors fall under for the 600 amp switch in the main building? I see that the 600 has no OCPD.
It's possible (though unlikely, I grant you) that the conductors to the 600A tap are adequately rated for the 2000A protection.

Or someone installed the 600A disc and 600A fused disc the wrong way round...
 
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