Subpanel

[jjason]

Does a small 8 space subpanel require a main in it?

 

[George Stolz]

Depends. What's the application?

 

[tom baker]

Under the 2008 NEC, a main can be part of the panel or in the supply to the panel.
Is this for a service, or a feeder panel in a separate building?
Whats a subpanel? Is that on a sub? (Sorry - thats a surface navy guy talking). The NEC does not use the term subpanel.

 

[jjason]

277/480 to transformer to 208/120 panel from this panel to my "subpanel" in an office, all in the same building

 

[George Stolz]

No main required.

 

[Pierre C Belarge]

A panel that is supplied from an overcurrent device protecting the conductors, is properly sized to the overcurrent protective device ahead of it and is located in the same building/structure is not required to have a main disconnect.
408.36

 

[iwire]

I agree with George and Pierre about the panel but you also mentioned a transformer and that may need secondary protection which is often accomplished with a main breaker in the panel the transformer supplies.

More details needed.

 

[jjason]

Transformer has ocp on primary and secondary, No Main then, Thanks

 

[Pierre C Belarge]

Transformer has ocp on primary and secondary, No Main then, Thanks

How is the ocp provided on the secondary side?

 

[jjason]

There is a 480 breaker suppling the Trans. then into the main of the 208 panel

 

[charlie b]

Since there is a breaker in the 208V panel feeding your sub panel, and since they are in the same building (i.e., no separate building disconnect is needed), then the sub panel does not need a main. I could have just said that I agree with the others, but I get paid by the word. :wink: