OCPD- two on a feeder? Main breaker or lugs?

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milemaker13

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Suburbs of Chicago
A co-worker and I are evaluating a new breaker box install in our press area of the shop. When discussing wheather this breaker box should have a main breaker or lugs we couldn't both come up with the same answer for the same reasons. We started reading thru the book at art 215 and 220, but are not finding the info we need.

Can anyone discribe the conditions that would require a main breaker vs main lugs?

This will be a 200 amp, 480 volt 3 wire breaker box. It is fed from the main service panel with a 200 amp fused switch. We plan to run 3/0 about 120'.

The new box will feed various process equipment in the area.
 
Check 408.36 and 450.14. Those two sections should help you decide.
 
408.36 says that my lugs would have to be at least 2" apart, correct?

I'm not sure how 450 applies to my question? It is dealing with transformers. I'm ashamed to admit, but I am still reading a 2002 code book (I've been asking for a new one, maybe now they will listen:happyno::happyyes:). My book does not have 450.14, stops at 450.13.
 
I'm now reading 408.16 (B). There will be no neutral, but currently 100% of its breakers will be 30 amps. 408.16(B) says AND, not OR.

Even if it were to be considered a lighting and appliance panel, 408.16(A), the fuses are 200 amp as the panel will be.

So... main lugs are OK?
 
Let me start over..............
408.36 states that the panel must have an overcurrent device . The device can be located within or at the point of supply. (as always, there are exceptions )
450.14 details the requirements for a disconnect means to be in sight from or lockable.
(408.16 was not mentioned)
 
My apology for bringing Art 450 into the thread. Old age, I guess.. somehow I read a transformer into the original thread.
The 408.36 is the appropriate thread and Cow is correct, as long as the panel is protected internally or at the source of the feeder, it is compliant.
 
Thanks guys. I appreciate the help. We both thought lugs would be ok, but couldn't really agree why lugs would be ok. :lol:

BTW- A new code book is on my material list for this project:thumbsup:
 
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