too many main breakers

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readydave8

re member
Location
Clarkesville, Georgia
Occupation
electrician
A friend had a job fail inspection. The building was put together with modular units, the units came with 200 amp main breaker panels. My friend mounted 200 amp mbp's with 8 spaces and feedthru lugs (trailer panels) on the exterior. These were fed from a 1600 amp service, 200 amp breakers in a distribution panel.

The inspector (North Carolina) said there was a limit of 2 main breakers, and my friend took the 200 amp main breakers out of the factory installed mbp's and put in main lug kits to pass inspection.

Where is this in the NEC?
 

KevinVost

Senior Member
Location
Las Vegas
A temp building or permanent??? I'm not sure I follow the install but it sounds like the 1600A service had 8 breakers. If so your friend has exceded the six switch rule (230.71). If the install was a breaker at the main and then an additional main breaker at the downstream panel, I don't believe there is a violation. As far as the single main breaker, the inspector may be in 550.11 (A) for mobile/manufactured homes. I don't know if this section would apply. IMO, building one structure out of several smaller modular ones would be no different than a strip mall with multiple tenents. I'm sure others will chime in that may know better.
 
A friend had a job fail inspection. The building was put together with modular units, the units came with 200 amp main breaker panels. My friend mounted 200 amp mbp's with 8 spaces and feedthru lugs (trailer panels) on the exterior. These were fed from a 1600 amp service, 200 amp breakers in a distribution panel.

The inspector (North Carolina) said there was a limit of 2 main breakers, and my friend took the 200 amp main breakers out of the factory installed mbp's and put in main lug kits to pass inspection.

Where is this in the NEC?

He Should have asked the inspector for a code reference. It could be a local code. I do not know of any in the NEC. It only deals with a maxium of 6 discos to turn off a building or structure. 2008 NEC 225.33
 

infinity

Moderator
Staff member
Location
New Jersey
Occupation
Journeyman Electrician
So you have a 1600 amp main breaker feeding 200 amp CB in the MDP feeding a 200 amp in the panel? Three breakers?
 

readydave8

re member
Location
Clarkesville, Georgia
Occupation
electrician
So you have a 1600 amp main breaker feeding 200 amp CB in the MDP feeding a 200 amp in the panel? Three breakers?

sorry, I was'nt reading carefully. 1600 amp main breaker, 200 amp I line breaker from it, 200 amp at outside disconnect, 200 amp inside in panel installed by manufactorer of modular unit. Remember that I had no part of any of this and am quoting my friend's experience. Thanks for your patience.
 

KevinVost

Senior Member
Location
Las Vegas
sorry, I was'nt reading carefully. 1600 amp main breaker, 200 amp I line breaker from it, 200 amp at outside disconnect, 200 amp inside in panel installed by manufactorer of modular unit. Remember that I had no part of any of this and am quoting my friend's experience. Thanks for your patience.

I don't see a violation, however this would be a fairly expensive install.
 

daleuger

Senior Member
Location
earth
I don't see how that is more than six to shut off any single structure. Yes, rather expensive install but it can be shut off at the panel or at the service. Either one would turn off the power to that structure unless I'm missing something too. :-?

Seen plenty and done a few installs where you have a multiple gang meter pack with xxx-amp breaker on the meter pack as well as a main in the individual panels. Is this any different?
 

hurk27

Senior Member
A friend had a job fail inspection. The building was put together with modular units, the units came with 200 amp main breaker panels. My friend mounted 200 amp mbp's with 8 spaces and feedthru lugs (trailer panels) on the exterior. These were fed from a 1600 amp service, 200 amp breakers in a distribution panel.

The inspector (North Carolina) said there was a limit of 2 main breakers, and my friend took the 200 amp main breakers out of the factory installed mbp's and put in main lug kits to pass inspection.

Where is this in the NEC?

His Mis-interpretation comes from 408-16(A) (2002)

This requirment was for parallel OCPD's protecting the panel board. this has nothing to do with this install, that also follows under 545 of the NEC.
 
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readydave8

re member
Location
Clarkesville, Georgia
Occupation
electrician
I'm sure that's it, thanks, I thought I had seen it but couldn't find it. I brought my '08 code book home with me so won't be able to look it up til I get back to the office. I'm gonna look smart when I tell my friend!
 
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