main breaker in sub panel

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madchad

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What situation determines whether or not you need to install a main breaker in a sub panel? After reading old posts I have determined that you do not need a main breaker in a sub panel if it is in the same building. Is this correct? What article can I refer to?
 
Re: main breaker in sub panel

volt,
The panel location does not have anything to do with the question "does the panel need a main?". The building will in most cases be required to have a disconenct by 225.31 and the easiest way to provide that disconnect would be by providing a main in the panel, but there are other methods and the code does not require that the panel have a main.
Don
 
Re: main breaker in sub panel

IMO,I feel like the location of the subpanel does make a difference.Lets say you have a 200amp main breaker panel in the house and you wanted to add a subpanel,load allowing a breaker could be installed in this main panel and extended to a main lug subpanel because it is within the same building (408.16).On the other hand, if a breaker was installed in this panel to feed a subpanel located in a detached garage then I feel like 225.31 applies and a main breaker at the detached garage panel is required,is this not correct?
 
Re: main breaker in sub panel

don,
Since madchad is asking about a sub-panel, It requires a feeder to feed it. The overcurrent protection required by 408.16 is normally covered by 215.3. The feeder needs overcurrent, it is common for the feeder to be sized at/or under the panel's rating. I am under the impression that madchad is using the "is a main breaker required" wording, meaning "is a disconnect required?" This brings back the question "where is the panel located?"

215.3 225.31 408.16

But if madchad is using this sub as a power panel and not a lighting an appliance branch circuit panelboard, then that is another question altogether.
 
Re: main breaker in sub panel

jap2525
I feel like the location of the subpanel does make a difference. ... I feel like 225.31 applies and a main breaker at the detached garage panel is required,is this not correct?
Click to expand...
Yes, 225.31 required a disconnect at the second building, and yes the easiest way to comply with 225.31 would be to install a main in the second building panel, but no, 225.31 does not require a main in the second building panel. It only requires a means of disconnect at the second builing. This can be accomplished by means other than a main breaker in the second building panel.
Don
 
Re: main breaker in sub panel

volt,
This brings back the question "where is the panel located?"
Click to expand...
Even if a disconnect is required, there is nothing that says, you must use a main breaker to provide the means of disconnect.
Don
 
Re: main breaker in sub panel

All panels are in the same building.

volt, Would it really make a difference if the classification of this panel was a power panelboard?
 
Re: main breaker in sub panel

well, that brings up a valid point, considering that you said sub-panel , i guess not...that exception only applies to service equipment...thanks for pointing that out...
 
Re: main breaker in sub panel

Your right Don,disconnecting means at the 2nd building is the right wording.(most generally a main breaker panel but not always).
 
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