residential building - panelboard main breakers

[debest]

Is there a requirement for main breakers in panelboards located on seperate floors of a residential building?

This is a rehab project where the plan was the reuse the existing panelboards which did not have main breakers. Each panelboard is fed from individual breakers located in a main power distribution board on the ground floor. The panelboards on each floor feed additional panelboards in each living area.

Thanks for your help!

 

[charlie b]

Re: residential building - panelboard main breakers

No.

The individual breakers in the main panel are there to protect the feeder to the sub-panels. In addition, the breaker must be rated at or below the rating of the sub-panel. But you do not need a main breaker in any of the sub-panels (i.e., they can be "Main Lug Only" - MLO), even if they are on a different floor from the main panel.

 

[don_resqcapt19]

Re: residential building - panelboard main breakers

Take a look at 240.24(B). This could require the use of a main in some cases.
Don